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Objective: Metabolic changes in type 1 diabetes mellitus (TIDM) impair vasodilation, and this leads to tissue hypoxia and microvascular pathology. Hyperbaric oxygen therapy (HBOT) can significantly improve the outcome of ischemic conditions in T1DM patients and reduce vascular complications. The aim of our study was to assess the effects of HBOT on plasma fatty acid (FA) composition, and expression of insulin-like growth factor binding protein 1 (IGFBP-1) in T1DM patients. Methods: Our study included 24 adult T1DM patients diagnosed with peripheral vascular complications. The patients were exposed to 10 sessions of 100% oxygen inhalation at 2.4 atmosphere absolute for 1 hour. Blood samples were collected at admission and after HBOT for measurement of metabolic parameters, FA composition and IGFBP-1. Measurement of plasma FA composition was determined by gas chromatography. Expression of IGFBP-1 in the serum was estimated by Western blot analysis. Results: HBOT decreased blood levels of total cholesterol (p lt 0.05), triglycerides (p lt 0.05) and low-density lipoprotein (p lt 0.05). HBOT increased plasma levels of individual FAs: palmitic acid (p lt 0.05), palmitoleic acid (p lt 0.05), docosapentaenoic acid (p lt 0.05) and docosahexaenoic acid (p lt 0.01), and decreased levels of stearic acid (p lt 0.05), alpha linolenic acid (p lt 0.05) and linoleic acid (p lt 0.01). Expression of IGFBP-1 (p lt 0.01) was increased, whereas the level of insulin (p lt 0.001) was decreased in the serum after HBOT. Conclusions: Our results indicate that HBOT exerts beneficial effects in TIDM patients by improving the lipid profile and altering FA composition.

Vascular complications in patients with diabetes mellitus (DM) are common. Since impaired oxygen balance in plasma plays an important role in the pathogenesis of chronic DM-associated complications, the administration of hyperbaric oxygen therapy (HBOT) has been recommended to influence development of vascular complications. Hyperbaric oxygen therapy involves inhalation of 100% oxygen under elevated pressure from 1.6 to 2.8 absolute atmospheres in hyperbaric chambers. Hyperbaric oxygen therapy increases plasma oxygen solubility, contributing to better oxygen diffusion to distant tissues and preservation of the viability of tissues reversibly damaged by atherosclerosis-induced ischemia, along with microcirculation restoration. Hyperbaric oxygen therapy exerts antiatherogenic, antioxidant, and cardioprotective effects by altering the level and composition of plasma fatty acids and also by promoting signal transduction through membranes, which are impaired by hyperglycemia and hypoxia. In addition, HBOT affects molecules involved in the regulation of nitric oxide synthesis and in that way exerts anti-inflammatory and angiogenic effects in patients with DM. In this review, we explore the recent literature related to the effects of HBOT on DM-related vascular complications.

Controlled ovarian stimulation (COS) is used to augment the number of retrieved oocytes in in vitro fertilization (IVF). Follicular fluid (FF) contributes significantly to oocyte quality. Since the FF is composed of follicular secretions and plasma exudation, it reflects alterations in granulosa and thecal cells secretion as well as changes in the level of plasma constituents. Phospholipids (PL) and free fatty acids (FFA) are important constituents of both, FF and serum. Our hypothesis is that COS affects the level of PL and FFA in serum. Furthermore, since the level of PL and FFA in FF partially depends on their levels in serum, as a collaterally of our hypothesis is that the existing level of PL and FFA in serum correlates with the levels of PL and FFA in FF, and that the dose of applied gonadotropins during COS will correlate with the levels of PL and FFA in serum and FF. In addition, we assume that the level of PL and FFA in serum and in FF after COS will correlate with the retrieved number of GQ oocytes, one of the most important outcomes of COS.. © 2018

Nitric oxide (NO) is a free radical which, in reactions with various molecules causes multiple biological effects. NO is exceptionally regulated and extends to almost every cell type and function within circulation. Generation and actions of NO are regulated by various hormones under physiological and pathophysiological conditions. Nitric oxide synthases (NOS) are the enzymes responsible for NO generation. In mammals, neuronal NOS (nNOS) and endothelial NOS (eNOS) are constitutively expressed, while inducible NOS (iNOS) mediate in immune defense. Altered NO level is associated with obesity, insulin resistance (IR), diabetes and cardiovascular diseases (CVD). Disturbances in eNOS and iNOS regulation accompany multiple changes in endothelial function and contribute to development of CVD. Furthermore, key step in initiation and progression of atherosclerosis is reduction in bioactivity of endothelial cell-derived NO. Here we shall focus on recent literature data related to the role of eNOS and iNOS in physiological and pathophysiological conditions. © 2018 Nova Science Publishers, Inc. All rights reserved.

Apoptosis may contribute to a significant proportion of neuron death following acute brain ischemia (ABI), but the underlying mechanisms are still not fully understood. Brain ischemia may lead to stroke, which is one of the main causes of long-term morbidity and mortality in both developed and developing countries. Therefore, stroke prevention and treatment is clinically important. There are two important separate areas of the brain during ABI: the ischemic core and the ischemic penumbra. The ischemic core of the brain experiences a sudden reduction of blood flow, just minutes after ischemic attack with irreversible injury and subsequent cell death. On the other hand, apoptosis within the ischemic penumbra may occur after several hours or days, while necrosis starts in the first hours after the onset of ABI in the ischemic core. ABI is characterized by key molecular events that initiate apoptosis in many cells, such as overproduction of free radicals, Ca2+ overload and excitotoxicity. These changes in cellular homeostasis may trigger either necrosis or apoptosis, which often depends on cell type, cell age, and location in the brain. Apoptosis results in DNA fragmentation, degradation of cytoskeletal and nuclear proteins, cross-linking of proteins, formation of apoptotic bodies, expression of ligands for phagocytic cell receptors and finally uptake by phagocytic cells. This review focuses on recent findings based on animal and human studies regarding the apoptotic mechanisms of neuronal death following ABI and the development of potential neuroprotective agents that reduce morbidity. The effects of statins on stroke prevention and treatment as well as on apoptotic mediators are also considered.

Metabolic syndrome (MetS) is a leading public health and clinical challenge worldwide. MetS represents a group of interrelated risk factors that predict cardiovascular diseases (CVD) and diabetes mellitus (DM). Its prevalence ranges between 10 and 84%, depending on the geographic region, urban or rural environment, individual demographic characteristics of the population studied (sex, age, racial and ethnic origin), as well as the criteria used to define MetS. Persons with MetS have higher mortality rate when compared with people without MetS, primarily caused by progressive atherosclerosis, accelerated by pro-inflammatory and pro-coagulation components of MetS. Considering the high prevalence of metabolic disorders (glucose metabolism disorder, hypertension, dyslipidaemia, obesity etc.), preventive healthcare should focus on changing lifestyle in order to reduce obesity and increase physical activity. This narrative review considers the available evidence from clinical and experimental studies dealing with MetS, and current treatment options for patients with insulin resistance and MetS.

Atherosclerosis is a life-long illness that begins with risk factors, which in turn contribute to the development of subclinical disease, followed by the establishment of overt cardiovascular disease (CVD). Thrombotic-occlusive complications of atherosclerosis are among the most widespread and costly health problems. Oxidized low-density lipoprotein (OxLDL) plays an important role in atherogenesis by promoting an inflammatory environment and lipid deposition in the arterial wall. As cardiovascular events occur in individuals without common risk factors, there is a need for additional tools that may help in CVD risk assessment and management. The use of biomarkers has improved diagnostic, therapeutic and prognostic outcome in cardiovascular medicine. This review elaborates on the value of circulating OxLDL as a biomarker of CVD. Three enzyme-linked immunosorbent assays (4E6, DLH3 and E06) using murine monoclonal antibodies for determination of OxLDL blood levels have been developed. However, none of these assays are currently approved for routine clinical practice. We identified studies investigating OxLDL in CVD (measured by 4E6, DLH3 or E06 assay) by searching the PubMed database. Circulating OxLDL was found to be associated with all stages of atherosclerosis, from early atherogenesis to hypertension, coronary and peripheral arterial disease, acute coronary syndromes and ischemic cerebral infarction. The results of studies investigating the usefulness of OxLDL for CVD prediction were also summarized. Furthermore, OxLDL was found to be associated with pathologic conditions linked to CVD, including diabetes mellitus, obesity and metabolic syndrome (MetS). In addition, we have addressed the mechanisms by which OxLDL promotes atherogenesis, and the effects of antiatherogenic treatments on circulating OxLDL. Finally, we highlight the evidence suggesting that lipoprotein (a) [ Lp(a)] is the preferential carrier of oxidized phospholipids (OxPL) in human plasma. A strong a

The assessment of cardiovascular risk and treatment of cardiovascular diseases are major public health issues worldwide. Inflammation is now recognized as a key regulatory process that links multiple risk factors for atherosclerosis. The substantial number of patients having cardiovascular events lack commonly established risk factors. The utility of high-sensitivity C-reactive protein (hsCRP), a circulating biomarker related to inflammation, may provide additional information in risk prediction. This review will consider the impact of hsCRP level on initiation of statin therapy.

An altered hepatic lipid metabolism involves multifactorial pathologies such as hepatic inflammation, insulin resistance and oxidative stress. Immunity has an essential role in the regulation of glucose and lipid metabolism in the liver. Inducible nitric oxide (NO) synthase (iNOS) has been proposed as an important factor that interplays between immunity and energy metabolism and also in the pathogenesis of obesity-linked insulin resistance. In the liver, locally produced NO plays a protective role during inflammation, and the balance of NO protective and cytotoxic effects is very important. This review is focused on understanding the molecular mechanisms of iNOS regulation in the state of altered hepatic lipid metabolism, which is critical for developing new strategies for treatment of hepatic disorders.

It is now recognized that inflammatory processes regulate all stages of atherosclerosis, from disease initiation to thrombotic complications. C-reactive protein (CRP) is a plasmatic protein used as a general marker of inflammation. The high sensitivity C-reactive protein (hsCRP) refers to the measurement of CRP in blood samples using assays with sufficient sensitivity to quantify low (baseline) levels of this biomarker. Low-grade chronic inflammatory processes are linked to atherosclerosis and may be screened with the use of hsCRP, thus providing additional information in cardiovascular risk prediction. This review elaborates the role of CRP in atherogenesis and the value of hsCRP as a biomarker in cardiovascular risk prediction in both primary and secondary prevention setting.

Estrogens have been recognized, in the last 3 decades, as important hormones in direct and indirect modulation of vascular health. In addition to their direct benefit on cardiovascular health, the presence of esterified estrogen in the lipid core of high-density lipoprotein (HDL) particles indirectly contributes to atheroprotection by significantly improving HDL quality and functionality. Estrogens modulate their physiological activity via genomic and nongenomic mechanisms. Genomic mechanisms are thought to be mediated directly by interaction of the hormone receptor complex with the hormone response elements that regulate gene expression. Nongenomic mechanisms are thought to occur via interaction of the estrogen with membrane-bound receptors, which rapidly activate intracellular signaling without binding of the hormone receptor complex to its hormone response elements. Estradiol in particular mediates early and late endothelial nitric oxide synthase (eNOS) activation via interaction with estrogen receptors through both nongenomic and genomic mechanisms. In the vascular system, the primary endogenous source of nitric oxide (NO) generation is eNOS. Nitric oxide primarily influences blood vessel relaxation, the heart rate, and myocyte contractility. The abnormalities in expression and/or functions of eNOS lead to the development of cardiovascular diseases, both in animals and in humans. Although considerable research efforts have been dedicated to understanding the mechanisms of action of estradiol in regulating cardiac eNOS, more research is needed to fully understand the details of such mechanisms. This review focuses on recent findings from animal and human studies on the regulation of eNOS and HDL quality by estradiol in cardiovascular pathology.

The pathogenesis of acute brain ischemia (ABI) is highly complex and involves multiple mechanisms including free radical generation. Imbalance between the cellular production of free radicals and the ability of cells to defend against them is referred to as oxidative stress. Oxidative stress is one of the mechanisms contributing to neuronal damage, potentially induced through the ABI. Through interactions with a large number of molecules, reactive oxygen species may irreversibly destroy or alter the function of the cellular lipids, proteins, and nucleic acids and initiate cell signaling pathways after cerebral ischemia. Future investigations should focus on the understanding of oxidative stress mechanisms and neuro-protection in order to discover new treatment targets.

Acute brain ischemia caused by transient ischemic attack initiates a complex sequence of events in the central nervous system and hypothalamic-pituitary-adrenal (HPA) axis which may ultimately culminate in neuronal and cell damage. The brain is highly susceptible to ischemia and in response to stress shows changes in morphology and chemistry that are largely reversible. These responses are known to modify the function of the HPA axis, but their mechanisms are not yet clear. Duration and size of the HPA axis activation are regulated by corticotropin-releasing hormone, vasopressin (AVP), and glucocorticoids, including cortisol. Numerous studies suggest that activation of these hormones following brain ischemia can result in neurohormonal dysfunction that can exacerbate long-term prognosis following stroke. These studies represent evidence that changes in the HPA axis play an important role in brain ischemia.

Estrogens are secreted primarily by the ovaries and placenta, by the testes in men and also produced by peripheral steroidogenic conversion. The 3 major naturally occurring estrogens are: 17 beta-estradiol (E-2), estrone and estriol, of which E-2 is the predominant and most active. The actions of E-2 are mediated by at least 3 different receptors - the classical ERs (ER alpha and ER beta) and G-protein coupled receptor 30 (GPR30). E-2 signaling in cardiomyocytes involves ER alpha- and ER beta-independent pathways, and treatment with the E-2 receptor antagonists (Selective Estrogen Receptor Modulators- SERMs), which are agonists of GPR30, inhibits cardiac cell growth. Effects of E-2 in preventing endothelial dysfunction, a prerequisite of atherosclerosis, are well recognized. Atherosclerosis involves interaction between the cells of the arterial wall endothelial cells (EC) and vascular smooth muscle cell (VSMC), as well as migration of macrophages into wall tunica media. It is predominantly developed at sites with abnormally high shear stress, such as bifurcations or branching of arteries, initiated by an injury to the endothelium and exposure to atherogenic lipids and toxins, such as those contained in tobacco smoke or infectious agents. Animal studies have shown effects of E-2 in preventing atherosclerosis, inflammation and endothelial or vascular dysfunction. Gender differences along this pathogenic pathway have been also described. We review the data from the available animal and human studies, which focus on anti-atherogenic effects of E-2. These studies represent evidence, albeit indirect, for an inhibitory effect of E-2 on the progression of coronary artery atherosclerosis.