Biochemical and Biophysical in Vitro Studies and Systematic Literature Review on the Antioxidant and Antiglycation Activities of Trazodone.

BACKGROUND/AIMS: Trazodone is a selective serotonin reuptake inhibitor; however, other mechanisms of the drug's anti-depressive properties have also been postulated. Hence, the aim of the study was to perform a systematic review and assess antiglycoxidative properties of trazodone in in vitro models. METHODS: Trazodone's scavenging and chelating properties were measured with spectrophotometric method. The impact of the drug on carbonyl/oxidative stress was marked in the bovine serum albumin (BSA) model where sugars (glucose, fructose, galactose, ribose) and aldehydes (glyoxal and methylglyoxal) were used as glycation agents. Aminoguanidine and N-acetylcysteine (NAC) were applied as reference glycation/free radical inhibitors. Glycation biomarkers (kynurenine, N-formylkynurenine, dityrosine as well as advanced glycation end products contents) were assessed spectrofluorometrically. Concentrations of oxidation parameters (total thiols (TTs), protein carbonyls (PCs) and also advanced oxidation protein products (AOPPs) levels) were determined spectrophotometrically. RESULTS: We demonstrated that trazodone poorly scavenged radicals (hydroxyl radical, nitric oxide, hydrogen peroxide and 2,2-diphenyl-1-picrylhydrazyl radical) and showed low ferrous ion chelating, unlike aminoguanidine and NAC. Sugars/aldehydes caused enhancement of glycation parameters, as well as a decrease of TTs and an increase of PCs and AOPPs levels compared to BSA incubated alone. Trazodone did not reduce oxidation parameters to the baseline (BSA) and significantly exacerbated glycation markers in comparison with both BSA and BSA+glycators. The content of glycation products was markedly lower in aminoguanidine and NAC than in trazodone. The molecular docking of trazodone to BSA revealed its very low affinity, which may indicate non-specific binding of trazodone, facilitating the attachment of glycation factors. CONCLUSION: According to our findings, it may be concluded that trazodone poorly counteracts oxidation and intensifies glycation in vitro. A possible mechanism for antiglycoxidative effect of trazodone in vivo may be the enhancement of the body's adaptive response, as indicated by the results of our systematic review.

Association of Ischemia-Modified Albumin (IMA) in Saliva, Serum, and Urine with Diagnosis of Chronic Kidney Disease (CKD) in Children: A Case-Control Study.

BACKGROUND Ischemia-modified albumin (IMA) is a secreted biomarker for ischemic oxidative stress. This case-control study aimed to evaluate the association of ischemia-modified albumin (IMA) in saliva, serum, and urine with diagnosis of chronic kidney disease (CKD) in 24 children. MATERIAL AND METHODS The study involved 24 children with CKD. CKD was defined according to the Kidney Disease Improving Global Outcomes (KDIGO) diagnostic criteria. The control group consisted of 24 healthy children who were matched for age and gender to the experimental group. The concentration of IMA was determined by the colorimetric method in non-stimulated whole saliva (NWS), stimulated whole saliva (SWS), serum, and urine of children with CKD. The Mann-Whitney U test was used for inter-group comparisons. RESULTS IMA levels were significantly higher in NWS (P=0.0082) and SWS (P=0.0014) of children with CKD than in the control group. The concentration of IMA in NWS was correlated with standard indicators of kidney function, including the estimated glomerular filtration rate (r=-0.798, P≤0.0001), stage of CKD (r=0.814, P≤0.0001), and serum creatinine (r=0.711, P≤0.0001) and urea levels (r=0.738, P≤0.0001). CONCLUSIONS Salivary IMA concentration depends on renal function in children. Salivary IMA discriminates children with end-stage kidney disease from children with mild and moderate CKD and healthy children with high sensitivity and specificity. Further research is required, including assessment of the diagnostic usefulness and validation of the biomarker in a clinical diagnostic study.

Antiglycoxidative properties of amantadine - a systematic review and comprehensive in vitro study.

An important drug used in the treatment of Parkinson's disease is amantadine. We are the first to perform a comprehensive study based on various glycation and oxidation factors, determining the impact of amantadine on protein glycoxidation. Sugars (glucose, fructose, galactose) and aldehydes (glyoxal, methylglyoxal) were used as glycation agents, and chloramine T was used as an oxidant. Glycoxidation biomarkers in albumin treated with amantadine were generally not different from the control group (glycation/oxidation factors), indicating that the drug did not affect oxidation and glycation processes. Molecular docking analysis did not reveal strong binding sites of amantadine on the bovine serum albumin structure. Although amantadine poorly scavenged hydroxyl radical and hydrogen peroxide, it had significantly lower antioxidant and antiglycation effect than all protein oxidation and glycation inhibitors. In some cases, amantadine even demonstrated glycoxidant, proglycation, and prooxidant properties. In summary, amantadine exhibited weak antioxidant properties and a lack of antiglycation activity.

Mitochondrial Redox Balance of Fibroblasts Exposed to Ti-6Al-4V Microplates Subjected to Different Types of Anodizing.

Despite the high biocompatibility of titanium and its alloys, the need to remove titanium implants is increasingly being debated due to the potential for adverse effects associated with long-term retention. Therefore, new solutions are being sought to enhance the biocompatibility of titanium implants. One of them is to increase the thickness of the passive layer of the implant made of titanium dioxide. We were the first to evaluate the effect of hard-anodized (type II) Ti-6Al-4V alloy discs on the cytotoxicity, mitochondrial function, and redox balance of fibroblasts mitochondria compared to standard-anodized (type III) and non-anodized discs. The study used fibroblasts obtained from human gingival tissue. The test discs were applied to the bottom of 12-well plates. Cells were cultured for 24 h and 7, 14, and 21 days and mitochondria were isolated. We demonstrated the occurrence of oxidative stress in the mitochondria of fibroblasts of all tested groups, regardless of the presence and type of anodization. Type II anodization prevented changes in complex II activity (vs. control). The lowest degree of citrate synthase inhibition occurred in mitochondria exposed to titanium discs with type II anodization. In the last phase of culture, the presence of type II anodization reduced the degree of cytochrome c oxidase inhibition compared to the other tests groups and the control group, and prevented apoptosis. Throughout the experiment, the release of titanium, aluminium, and vanadium ions from titanium discs with a hard-anodized passive layer was higher than from the other titanium discs, but decreased with time. The obtained results proved the existence of dysfunction and redox imbalance in the mitochondria of fibroblasts exposed to hard-anodized titanium discs, suggesting the need to search for new materials perhaps biodegradable in tissues of the human body.

Hypogelsolinemia and Decrease in Blood Plasma Sphingosine-1-Phosphate in Patients Diagnosed with Severe Acute Pancreatitis.

BACKGROUND: Acute pancreatitis (AP) is a frequent hospitalization cause of patients suffering from gastrointestinal disorders. Gelsolin has an ability to bind bioactive lipids including different sphingolipids engaged in inflammatory response. Importantly, hypogelsolinemia was observed in patients with different states of acute and chronic inflammation. AIMS: The aim of the present study was to assess the interplay of blood plasma gelsolin and blood plasma sphingosine-1-phosphate (S1P) concentration in patients diagnosed with acute pancreatitis. MATERIALS AND METHODS: To assess the concentration of gelsolin and S1P, immunoblotting and HPLC technique were employed, respectively. Additionally, the concentrations of amylase, lipase, C-reactive protein (CRP), procalcitonin (PCT) and the number of white blood cells (WBC) and platelet (PLT) were recorded. RESULTS: We found that both pGSN and S1P concentrations in the plasma of the AP patients were significantly lower (pGSN ~ 15-165 mg/L; S1P ~ 100-360 pmol/mL) when compared to the levels of pGSN and S1P in a control group (pGSN ~ 130-240 mg/L; S1P ~ 260-400 pmol/mL). Additionally, higher concentrations of CRP, WBC, amylase and lipase were associated with low level of gelsolin in the blood of AP patients. No correlations between the level of PCT and PLT with gelsolin concentration were noticed. CONCLUSION: Plasma gelsolin and S1P levels decrease during severe acute pancreatitis. Simultaneous assessment of pGSN and S1P can be useful in development of more accurate diagnostic strategies for patients with severe acute pancreatitis.

High Protein Diet Induces Oxidative Stress in Rat Cerebral Cortex and Hypothalamus.

This is the first study to analyze the impact of high protein diet (HPD) on antioxidant defense, redox status, as well as oxidative damage on both a local and systemic level. Male Wistar rats were divided into two equal groups (n = 9): HPD (44% protein) and standard diet (CON; 24.2% protein). After eight weeks, glutathione peroxidase (GPx), glutathione reductase (GR), catalase (CAT), superoxide dismutase-1 (SOD-1), reduced glutathione (GSH), uric acid (UA), total antioxidant (TAC)/oxidant status (TOS) as well as advanced glycation end products (AGE), 4-hydroxynonenal (4-HNE), and malondialdehyde (MDA) were analyzed in the serum/plasma, cerebral cortex, and hypothalamus of HPD and CON rats. HPD resulted in higher UA concentration and activity of GPx and CAT in the hypothalamus, whereas in the cerebral cortex these parameters remained unchanged. A significantly lower GSH content was demonstrated in the plasma and hypothalamus of HPD rats when compared to CON rats. Both brain structures expressed higher content of 4-HNE and MDA, whereas AGE was increased only in the hypothalamus of HPD animals. Despite the enhancement in antioxidant defense in the hypothalamus, this mechanism does not protect the hypothalamus from oxidative damage in rats. Hypothalamus is more susceptible to oxidative stress caused by HPD.

Challenging of AS160/TBC1D4 Alters Intracellular Lipid milieu in L6 Myotubes Incubated With Palmitate.

The Akt substrate of 160 kDa (AS160) is a key regulator of GLUT4 translocation from intracellular depots to the plasma membrane in myocytes. Likely, AS160 also controls LCFAs transport, which requires relocation of fatty acid transporters. The aim of the present study was to determine the impact of AS160 knockdown on lipid milieu in L6 myotubes incubated with palmitate (PA). Therefore, we compared two different settings, namely: 1) AS160 knockdown prior to palmitate incubation (pre-PA-silencing, AS160- /PA); 2) palmitate incubation with subsequent AS160 knockdown (post-PA-silencing, PA/AS160- ). The efficiency of AS160 silencing was checked at mRNA and protein levels. The expression and localization of FA transporters were determined using Western Blot and immunofluorescence analyses. Intracellular lipid content (FFA, DAG, TAG, and PL) and FA composition were estimated by GLC, whereas basal palmitate uptake was analyzed by means of scintigraphy. Both groups with silenced AS160 were characterized by a greater expression of FA transporters (FAT/CD36, FATP-1, 4) which had contributed to an increased FA cellular influx. Accordingly, we observed that post-PA-silencing of AS160 resulted in a marked decrement in DAG, TAG, and PL contents, but increased FFA content (PA/AS160- vs. PA). The opposite effect was observed in the group with pre-PA-silencing of AS160 in which AS160 knockdown did not affect the lipid pools (AS160- /PA vs. PA). Our results indicate that post-PA-silencing of AS160 has a capacity to decrease the lipotoxic effect(s) of PA by decreasing the content of lipids (DAG and PL) that promote insulin resistance in myotubes. J. Cell. Physiol. 232: 2373-2386, 2017. © 2016 The Authors. Journal of Cellular Physiology Published by Wiley Periodicals Inc.

Sphingolipids metabolism in the salivary glands of rats with obesity and streptozotocin induced diabetes.

Diabetes is considered a major public health problem affecting millions of individuals worldwide. Remarkably, scientific reports regarding salivary glands sphingolipid metabolism in diabetes are virtually non-existent. This is odd given the well-established link between the both in other tissues (e.g., skeletal muscles, liver) and the key role of these glands in oral health preservation. The aim of this paper is to examine sphingolipids metabolism in the salivary glands in (pre)diabetes (evoked by high fat diet feeding or streptozotocin). Wistar rats were allocated into three groups: control, HFD-, or STZ-diabetes. The content of major sphingolipid classes in the parotid (PSG) and submandibular (SMSG) glands was assessed via chromatography. Additionally, Western blot analyses were employed for the evaluation of key sphingolipid signaling pathway enzyme levels. No changes in ceramide content in the PSG were found, whereas an increase in ceramide concentration for SMSG of the STZ group was observed. This was accompanied by an elevation in SPT1 level. Probably also sphingomyelin hydrolysis was increased in the SMSG of the STZ-diabetic rats, since we observed a significant drop in the amount of SM. PSG and SMSG respond differently to (pre)diabetes, with clearer pattern presented by the later gland. An activation of sphingomyelin signaling pathway was observed in the course of STZ-diabetes, that is, metabolic condition with rapid onset/progression. Whereas, chronic HFD lead to an inhibition of sphingomyelin signaling pathway in the salivary glands (manifested in an inhibition of ceramide de novo synthesis and accumulation of S1P).

Unexpected profile of sphingolipid contents in blood and bone marrow plasma collected from patients diagnosed with acute myeloid leukemia.

BACKGROUND: Impaired apoptotic pathways in leukemic cells enable them to grow in an uncontrolled way. Moreover, aberrations in the apoptotic pathways are the main factor of leukemic cells drug resistance. METHODS: To assess the presence of potential abnormalities that might promote dysfunction of leukemic cells growth, HPLC system was used to determine sphingosine (SFO), sphinganine (SFA), sphingosine-1-phosphate (S1P) and ceramide (CER) concentration in the blood collected from patients diagnose with acute myeloblastic leukemia (AML; n = 49) and compare to values of control (healthily) group (n = 51). Additionally, in AML group concentration of SFO, SFA, S1P and CER was determined in bone marrow plasma and compared to respective values in blood plasma. The concentration of S1P and CER binding protein - plasma gelsolin (GSN) was also assessed in collected samples using immunoblotting assay. RESULTS: We observed that in AML patients the average SFO, SFA and CER concentration in blood plasma was significantly higher (p < 0.001) compare to control group, when blood plasma S1P concentration was significantly lower (p < 0.001). At the same time the CER/S1P ratio in AML patient (44.5 ± 19.4) was about 54% higher compare to control group (20.9 ± 13.1). Interestingly the average concentration of S1P in blood plasma (196 ± 13 pmol/ml) was higher compare to its concentration in plasma collected from bone marrow (154 ± 21 pmol/ml). CONCLUSIONS: We hypothesize that changes in profile of sphingolipids concentration and some of their binding protein partners such as GSN in extracellular environment of blood and bone marrow cells in leukemic patients can be targeted to develop new AML treatment method(s).

Plasma Sphingolipids in Acute Pancreatitis.

Acute pancreatitis (AP) is a prevalent gastrointestinal disorder associated with systemic inflammatory response syndrome and, in the case of severe AP, a mortality rate ranging from 36% to 50%. Standard clinical treatment of AP includes intensive hydration, analgesia, and management of complications. Unfortunately, the direct treatment of AP at the level of its molecular pathomechanism has not yet been established. Recent studies indicate that the sphingolipid signaling pathway may be one of the important factors contributing to the development of inflammation in pancreatic diseases. In the current study, we sought to investigate this promising route. We examined the plasma sphingolipid profile of 44 patients with acute pancreatitis, dividing them into three groups: mild, moderate and severe AP. Samples were collected from these groups at days 1, 3 and 7 following their hospital admission. We demonstrated significant changes in blood plasma sphingolipids in relation to the time course of AP. We also found an inhibition of de novo ceramide synthesis in mild and moderate AP. However, the most important and novel finding was a significant elevation in sphingosine-1-phosphate (S1P) (a downstream metabolite of ceramide) in mild AP, as well as a dramatic reduction in the lipid molecule content in the early stage (days 1 and 3) of severe AP. This strongly indicates that plasma S1P could serve as a prognostic marker of AP severity.

Sphingosine-1-Phosphate Metabolism and Its Role in the Development of Inflammatory Bowel Disease.

Beyond their role as structural molecules, sphingolipids are involved in many important cellular processes including cell proliferation, apoptosis, inflammation, and migration. Altered sphingolipid metabolism is observed in many pathological conditions including gastrointestinal diseases. Inflammatory bowel disease (IBD) represents a state of complex, unpredictable, and destructive inflammation of unknown origin within the gastrointestinal tract. The mechanisms explaining the pathophysiology of IBD involve signal transduction pathways regulating gastro-intestinal system's immunity. Progressive intestinal tissue destruction observed in chronic inflammation may be associated with an increased risk of colon cancer. Sphingosine-1-phosphate (S1P), a sphingolipid metabolite, functions as a cofactor in inflammatory signaling and becomes a target in the treatment of IBD, which might prevent its conversion to cancer. This paper summarizes new findings indicating the impact of (S1P) on IBD development and IBD-associated carcinogenesis.

The Effects of AS160 Modulation on Fatty Acid Transporters Expression and Lipid Profile in L6 Myotubes.

BACKGROUND/AIMS: AS160 is a key intracellular regulator of energy utilization in cells. It was shown to regulate GLUT4 translocation from intracellular depots to the plasma membrane, with subsequent changes in facilitated glucose uptake into the skeletal muscles. Similarly, also free fatty acids (FFAs) transmembrane transport seems to be largely protein-mediated. Therefore, the objective of this study was to examine the effects of moderate AS160 depletion (-82% mRNA, -25% of protein content) on the expression of fatty acid transporters and subsequent changes in lipid profile in L6 myotubes. RESULTS: Surprisingly, moderate down regulation of AS160 expression was followed by increased AS160 phosphorylation (∼40%). These resulted in a greater expression of fatty acid transporters, namely FABPpm and FAT/CD36, with subsequently increased FAs cellular influx. No changes in the expression of FATP1 and 4 were noticed. Accordingly, we have observed a reduction in total TAG content. This was mainly caused by a significant changes in TAG fatty acids composition favouring a decrease in the amount of palmitic and stearic fatty acid moieties. In contrast, our experimental intervention led to distinctively increased total content of DAG and PL, but concomitantly decreased the content of all measured sphingolipids, e.g. SFA, SA1P, CER, SFO and S1P, in the AS160 knockdown group. CONCLUSIONS: Modulation of AS160 level and activity led to significant increase in the concentration of DAG and PL, which was associated with changes in FAs composition and expression of fatty acid transporters. Interestingly, the intervention also simultaneously decreased the content of sphingolipids.

Effect of streptozotocin-induced diabetes on lipids metabolism in the salivary glands.

BACKGROUND: Diabetes is one of the most common metabolic diseases. Moreover, previous studies indicate that diabetes may cause changes in the salivary glands phenotype and in the composition of saliva itself. Therefore, the main objective of this study was to determine the effects of streptozotocin induced diabetes on lipid profile of the rat salivary glands. METHODS: Male Wistar rats were divided into two groups: control and STZ-induced diabetes. At the end of the experiment all animals were sacrificed and samples of the parotid and submandibular salivary glands were excised. Major lipid fractions concentrations were determined by means of chromatography (TLC and GC). RESULTS: We observed a significant increase (∼3.5 fold) in the level of triacylglycerol in both the parotid and submandibular salivary glands of diabetic rats. The abovementioned changes were accompanied by significant, although less dramatic (i.e. from -60% to -90%), decrements in the levels of other lipid classes (phospholipids, free fatty acids and diacylglycerol). CONCLUSIONS: In our study we have showed, presumably for the first time, that streptozotocin induced diabetes causes decrement in PH content with subsequent atrophy and malfunction in both parotid and submandibular salivary glands. Another novel finding of our research is that diabetic rats were characterized by an increased TG accumulation in both parotid and submandibular salivary glands. The later one could be a clinical manifestation of diabetes.

Impact of morbid obesity and bariatric surgery on antioxidant/oxidant balance of the unstimulated and stimulated human saliva.

OBJECTIVE: There is no study evaluating the influence of morbid obesity and bariatric surgery on antioxidant/oxidant homeostasis of the unstimulated and stimulated human saliva. MATERIALS AND METHODS: Salivary flow rate, total antioxidant status (TAS), total oxidant status (TOS), oxidative status index (OSI), the total amount of uric acid (UA), polyphenols (pPh), catalase (CAT), superoxide dismutase 2 (SOD2), specific activity of peroxidase (Px), as well as malondialdehyde (MDA), and advanced glycation end products (AGE) concentrations were determined in the unstimulated (UWS) and stimulated (SWS) whole saliva of patients with morbid obesity before and after bariatric surgery. RESULTS: In both UWS and SWS, the total amount of TOS, OSI, SOD2, and MDA was statistically higher in patients with morbid obesity as compared to the healthy controls, as well as significantly lower in the patients treated surgically as compared to the obese patients. The median values of the total amount of TAS, CAT, UA, pPh, and specific activity of Px were significantly reduced in UWS and SWS in patients with morbid obesity as compared to the control group and also statistically elevated in patients after bariatric surgery as compared to the patients with morbid obesity. CONCLUSIONS: In morbid obesity, reduced unstimulated and stimulated salivary flow can be observed. Bariatric surgery restored only unstimulated salivary flow to normal values. Disturbances in oxidant/antioxidant homeostasis may be observed in UWS and SWS of obese patients before and after treatment.

The Role of PGC-1α in the Development of Insulin Resistance in Skeletal Muscle - Revisited.

Currently, obesity is a predominant medical condition and an important risk factor for the development of several diseases, including type 2 diabetes mellitus. Importantly, most research has indicated lipid-induced insulin resistance in skeletal muscles is a key link between the aforementioned pathological conditions. PGC-1α is a prominent regulator of myocellular energy metabolism orchestrating gene transcription programming in response to numerous environmental stimuli. Moreover, it is widely acknowledged that mitochondrial metabolism (primary metabolic target of PGC-1α) disturbances are widely acknowledged contributors to type 2 diabetes development. Therefore, it seems surprising that the exact physiological contribution of PGC-1α in the development of insulin resistance in skeletal muscle remains poorly understood. This review aims to reconcile these allegedly different findings by looking for a common denominator in the role(s) of PGC-1α in respect to lipid-induced insulin resistance in skeletal muscle. Our scrutiny of the literature indicates that interventions at the level of PGC-1α may exert beneficial effects on myocytes in respect to lipid-induced insulin resistance. The latter takes place as a result of a positive net energy balance (fatty acids oxidation surpassing their accumulation rate). Moreover, the aforementioned effects may not necessarily be limited to physically active states. They seem to occur, however, only within a physiologically observed range in muscle cells (approximately 1-fold changes in PGC-1α protein expression).

Hyperthyroidism evokes myocardial ceramide accumulation.

BACKGROUND: Thyroid hormones (THs) are key regulators of cardiac physiology as well as modulators of different cellular signals including the sphingomyelin/ceramide pathway. The objective of this study was to examine the effect of hyperthyroidism on the metabolism of sphingolipids in the muscle heart. METHODS: Male Wistar rats were treated for 10 days with triiodothyronine (T3) at a dose of 50µg/100g of body weight. Animals were then anaesthetized and samples of the left ventricle were excised. RESULTS: We have demonstrated that prolonged, in vivo, T3 treatment increased the content of sphinganine (SFA), sphingosine (SFO), ceramide (CER) and sphingomyelin (SM), but decreased the level of sphingosine-1-phosphate (S1P) in cardiac muscle. Accordingly, the changes in sphingolipids content were accompanied by a lesser activity of neutral sphingomyelinase and without significant changes in ceramidases activity. Hyperthyroidism also induced activation of AMP-activated protein kinase (AMPK) with subsequently increased expression of mitochondrial proteins: cytochrome c oxidase IV (COX IV), ß-hydroxyacyl-CoA dehydrogenase (ß-HAD), carnityne palmitoyltransferase I (CPT I) and nuclear peroxisome proliferator-activated receptor-γ coactivator-1α (PGC1α). CONCLUSIONS: We conclude that prolonged T3 treatment increases sphingolipids metabolism which is reflected by higher concentration of SFA and CER in heart muscle. Furthermore, hyperthyroidism-induced increase in heart sphingomyelin (SM) concentration might be one of the mechanisms underlying maintenance of CER at relatively low level by its conversion to SM together with decreased S1P content.

Increased levels of sphingosine-1-phosphate in cerebrospinal fluid of patients diagnosed with tick-borne encephalitis.

BACKGROUND: Tick-borne encephalitis (TBE) is a serious acute central nervous system infection that can result in death or long-term neurological dysfunctions. We hypothesize that changes in sphingosine-1-phosphate (S1P) concentration occur during TBE development. METHODS: S1P and interleukin-6 (IL-6) concentrations in blood plasma and cerebrospinal fluid (CSF) were measured using HPLC and ELISA, respectively. The effects of S1P on cytoskeletal structure and IL-6 production were assessed using rat astrocyte primary cultures with and without addition of plasma gelsolin and the S1P receptor antagonist fingolimod phosphate (FTY720P). RESULTS: We report that acute inflammation due to TBE virus infection is associated with elevated levels of S1P and IL-6 in the CSF of infected patients. This elevated concentration is observed even at the earliest neurologic stage of disease, and may be controlled by glucocorticosteroid anti-inflammatory treatment, administered to patients unresponsive to antipyretic drugs and who suffer from a fever above 39°C. In vitro, treatment of confluent rat astrocyte monolayers with a high concentration of S1P (5 µM) results in cytoskeletal actin remodeling that can be prevented by the addition of recombinant plasma gelsolin, FTY720P, or their combination. Additionally, gelsolin and FTY720P significantly decreased S1P-induced release of IL-6. CONCLUSIONS: TBE is associated with increased concentration of S1P and IL-6 in CSF, and this increase might promote development of inflammation. The consequences of increased extracellular S1P can be modulated by gelsolin and FTY720P. Therefore, blocking the inflammatory response at sites of infection by agents modulating S1P pathways might aid in developing new strategies for TBE treatment.

Inhibition of ceramide de novo synthesis reduces liver lipid accumulation in rats with nonalcoholic fatty liver disease.

BACKGROUND & AIMS: Nonalcoholic fatty liver disease (NAFLD) is an insulin resistance-related hepatic disorder which can transform to cirrhosis. Insulin resistance deregulates hepatic lipid metabolism, leading to accumulation of cytotoxic lipids including ceramide and diacylglycerols. Myriocin, obtained from fungi traditionally used in Chinese medicine in an effort to attain eternal youth, is a potent pharmacological inhibitor of ceramide de novo synthesis. We examined whether inhibition of ceramide de novo synthesis with myriocin ameliorate hepatic lipid accumulation and reverse NAFLD. METHODS: The experiment was carried out on male Wistar rats. The animals were divided into four groups: (i) control group, fed standard rodent diet, (ii) group, fed standard diet also treated with myriocin for 7 days, (iii) group, fed high-fat diet for 5 weeks, (iv) group, fed high-fat diet and treated with myriocin. In liver samples sphingolipids: ceramide, sphingosine and sphingosine-1-phosphatate and neutral lipids, such as diacylglycerols and triacylglycerols were measured. In peripheral blood samples, glucose and insulin levels and aminotransferases activities were measured. RESULTS: High-fat diet feeding caused NAFLD, confirmed by histological assessment, with increased hepatic lipids accumulation and whole-body insulin resistance. After treating with inhibitor of ceramide de novo synthesis, decrease in hepatic ceramide and other toxic lipids were noticed. Moreover, histological analysis of liver samples revealed that inhibition of ceramide de novo synthesis reduced hepatic steatosis. CONCLUSIONS: Inhibition of ceramide de novo synthesis reduced hepatic lipid accumulation in rats with NAFLD, this led to amelioration of hepatic steatosis.

The antiglycation potential of H1 receptor antagonists - in vitro studies in bovine serum albumin model and in silico molecular docking analyses.

The H1 receptor belongs to the family of rhodopsin-like G-protein-coupled receptors activated by the biogenic amine histamine. H1 receptor antagonists are widely used in the treatment of allergies. However, these drugs could have a much broader spectrum of activity, including hypoglycemic effects, which can broaden the spectrum of their use. The aim of the study was to evaluate the antiglycation potential of twelve H1 receptor antagonists (diphenhydramine, antazoline, promethazine, ketotifen, clemastine, pheniramine, cetirizine, levocetirizine, bilastine, fexofenadine, desloratadine, and loratadine). Bovine serum albumin (BSA) was glycated with sugars (glucose, fructose, galactose, and ribose) and aldehydes (glyoxal and methylglyoxal) in the presence of H1 blockers. The tested substances did not induce a significant decrease in the content of albumin glycation end-products, and the inhibition rate of glycoxidation was not influenced by the chemical structure or generation of H1 blockers. None of the tested H1 receptor antagonists exhibited strong antiglycation activity. Antiglycemic potential of H1 blockers could be attributed to their antioxidant and anti-inflammatory activity, as well as their effects on carbohydrate metabolism/metabolic balance at the systemic level.

Novel Properties of Old Propranolol-Assessment of Antiglycation Activity through In Vitro and In Silico Approaches.

Hypertension has earned the "silent killer" nickname since it may lead to a number of comorbidities, including diabetes and cardiovascular diseases. Oxidative stress and protein glycation play vital roles in the pathogenesis of hypertension. Several studies have shown that they profoundly account for vascular dysfunction, endothelial damage, and disruption of blood pressure regulatory mechanisms. Of particular note are advanced glycation end products (AGEs). AGEs alter vascular tissues' functional and mechanical properties by binding to receptors for advanced glycation end products (RAGE), stimulating inflammation and free radical-mediated pathways. Propranolol, a nonselective beta-adrenergic receptor antagonist, is one of the most commonly used drugs to treat hypertension and cardiovascular diseases. Our study is the first to analyze propranolol's effects on protein glycoxidation through in vitro and in silico approaches. Bovine serum albumin (BSA) was utilized to evaluate glycoxidation inhibition by propranolol. Propranolol (1 mM) and BSA (0.09 mM) were incubated with different glycating (0.5 M glucose, fructose, and galactose for 6 days and 2.5 mM glyoxal and methylglyoxal for 12 h) or oxidizing agents (chloramine T for 1 h). Biomarkers of protein glycation (Amadori products (APs), ß-amyloid (ßA), and advanced glycation end products (AGEs)), protein glycoxidation (dityrosine (DT), kynurenine (KYN), and N-formylkynurenine (NFK)), protein oxidation (protein carbonyls (PCs), and advanced oxidation protein products (AOPPs)) were measured by means of colorimetric and fluorimetric methods. The scavenging of reactive oxygen species (hydrogen peroxide, hydroxyl radical, and nitric oxide) and the antioxidant capacity (2,2-diphenyl-1-picrylhydrazyl radical and ferrous ion chelating (FIC) assays)) of propranolol were also evaluated. Additionally, in silico docking was performed to showcase propranolol's interaction with BSA, glycosides, and AGE/RAGE pathway proteins. The products of protein glycation (↓APs, ↓ßA, ↓AGEs), glycoxidation (↓DT, ↓KYN, ↓NFK), and oxidation (↓PCs, ↓AOPPs) prominently decreased in the BSA samples with both glycating/oxidizing factors and propranolol. The antiglycoxidant properties of propranolol were similar to those of aminoguanidine, a known protein oxidation inhibitor, and captopril, which is an established antioxidant. Propranolol showed a potent antioxidant activity in the FIC and H2O2 scavenging assays, comparable to aminoguanidine and captopril. In silico analysis indicated propranolol's antiglycative properties during its interaction with BSA, glycosidases, and AGE/RAGE pathway proteins. Our results confirm that propranolol may decrease protein oxidation and glycoxidation in vitro. Additional studies on human and animal models are vital for in vivo verification of propranolol's antiglycation activity, as this discovery might hold the key to the prevention of diabetic complications among cardiology-burdened patients.