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Eff ect of a single asenapine treatment on Fos expression in the brain catecholamine-synthesizing neurons: impact of a chronic mild stress preconditioning

Abstract

Objective. Fos protein expression in catecholamine-synthesizing neurons of the substantia nigra (SN) pars compacta (SNC, A8), pars reticulata (SNR, A9), and pars lateralis (SNL), the ventral tegmental area (VTA, A10), the locus coeruleus (LC, A6) and subcoeruleus (sLC), the ventrolateral pons (PON-A5), the nucleus of the solitary tract (NTS-A2), the area postrema (AP), and the ventrolateral medulla (VLM-A1) was quantitatively evaluated aft er a single administration of asenapine (ASE) (designated for schizophrenia treatment) in male Wistar rats preconditioned with a chronic unpredictable variable mild stress (CMS) for 21 days. Th e aim of the present study was to reveal whether a single ASE treatment may 1) activate Fos expression in the brain areas selected; 2) activate tyrosine hydroxylase (TH)-synthesizing cells displaying Fos presence; and 3) be modulated by CMS preconditioning.

Methods. Control (CON), ASE, CMS, and CMS+ASE groups were used. CMS included restraint, social isolation, crowding, swimming, and cold. Th e ASE and CMS+ASE groups received a single dose of ASE (0.3 mg/kg, s.c.) and CON and CMS saline (300 μl/rat, s.c.). The animals were sacrificed 90 min aft er the treatments. Fos protein and TH-labeled immunoreactive perikarya were analyzed on double labeled histological sections and enumerated on captured pictures using combined light and fluorescence microscope illumination.

Results. Saline or CMS alone did not promote Fos expression in any of the structures investigated. ASE alone or in combination with CMS elicited Fos expression in two parts of the SN (SNC, SNR) and the VTA. Aside from some cells in the central gray tegmental nuclei adjacent to LC, where a small number of Fos profiles occurred, none or negligible Fos occurrence was detected in the other structures investigated including the LC and sLC, PON-A5, NTS-A2, AP, and VLM-A1. CMS preconditioning did not infl uence the level of Fos induction in the SN and VTA elicited by ASE administration. Similarly, the ratio between the amount of free Fos and Fos colocalized with TH was not aff ected by stress preconditioning in the SNC, SNR, and the VTA.

Conclusions. Th e present study provides an anatomical/functional knowledge about the nature of the acute ASE treatment on the catecholamine-synthesizing neurons activity in certain brain structures and their missing interplay with the CMS preconditioning.

Open access
Expression of genes encoding IGFBPs, SNARK, CD36, and PECAM1 in the liver of mice treated with chromium disilicide and titanium nitride nanoparticles

Abstract

Objective. The aim of the present study was to examine the effect of chromium disilicide and titanium nitride nanoparticles on the expression level of genes encoding important regulatory factors (IGFBP1, IGFBP2, IGFBP3, IGFBP4, IGFBP5, SNARK/NUAK2, CD36, and PECAM1/CD31) in mouse liver for evaluation of possible toxic effects of these nanoparticles.

Methods. Male mice received 20 mg chromium disilicide nanoparticles (45 nm) and titanium nitride nanoparticles (20 nm) with food every working day for 2 months. The expression of IGFBP1, IGFBP2, IGFBP3, IGFBP4, IGFBP5, SNARK, CD36, and PECAM1 genes in mouse liver was studied by quantitative polymerase chain reaction.

Results. Treatment of mice with chromium disilicide nanoparticles led to down-regulation of the expression of IGFBP2, IGFBP5, PECAM1, and SNARK genes in the liver in comparison with control mice, with more prominent changes for SNARK gene. At the same time, the expression of IGFBP3 and CD36 genes was increased in mouse liver upon treatment with chromium disilicide nanoparticles. We have also shown that treatment with titanium nitride nanoparticles resulted in down-regulation of the expression of IGFBP2 and SNARK genes in the liver with more prominent changes for SNARK gene. At the same time, the expression of IGFBP3, IGFBP4, and CD36 genes was increased in the liver of mice treated with titanium nitride nanoparticles. Furthermore, the effect of chromium disilicide nanoparticles on IGFBP2 and CD36 genes expression was significantly stronger as compared to titanium nitride nanoparticles.

Conclusions. The results of this study demonstrate that chromium disilicide and titanium nitride nanoparticles have variable effects on the expression of IGFBP2, IGFBP3, IGFBP4, IGFBP5, SNARK, CD36, and PECAM1 genes in mouse liver, which may reflect the genotoxic activities of the studied nanoparticles.

Open access
Premature ovarian failure could be an alarming sign of polyglandular autoimmune dysfunction

Abstract

A 31-year-old lady, diagnosed to have premature ovarian failure in the gynecology clinic, was referred for endocrine assessment because of an abnormal thyroid function test. Clinical examination revealed hypotension, and fungal skin infection under her atrophic breasts. Thyroid stimulating hormone (TSH) level was very high. Assessment of the suprarenal function revealed evidence of Addison’s disease. Polyglandular autoimmune dysfunction was diagnosed. She was treated with prednisone, fludrocortisone, and levothyroxine with significant improvement of her general condition and blood pressure.

Open access
The role of thyrostimulin and its potential clinical significance

Abstract

Thyrostimulin is a glycoprotein heterodimer of GPA2 and GPB5, first described in 2002. It is involved in the physiological function of several tissues. Moreover, evidence points towards the ability of thyrostimulin’s individual monomers to induce a biological effect, which could denote the circulatory/systemic effects of the molecule when found in higher concentrations. From the evolutionary point of view, thyrostimulin shares a binding epitope with the thyroid-stimulating hormone for the thyroid stimulating hormone receptor, whilst possessing affinity for another unique binding site on the same receptor. Although thyrostimulin can be involved in the hypothalamicpituitary- thyroid axis, its presence in various tissues in an eclectic array of different species renders it multifunctional. From weight loss via increasing metabolic rate to progression of cancer in human ovaries, it is certainly not a signaling molecule to overlook. Furthermore, thyrostimulin has been implicated in bone metabolism, acute illness, and reproductive function. In summary, to our knowledge, this is the first review dealing with the physiological role of thyrostimulin and its potential applications in the clinical practice.

Open access
Th e eff ects of Nigella Sativa extract on renal tissue oxidative damage during neonatal and juvenile growth in propylthiouracil-induced hypothyroid rats

Abstract

Objective. We investigated the effects of hydroalcoholic extract of Nigella sativa (NS) on renal tissue oxidative damage associated with propylthiouracil (PTU)-induced hypothyroidism during neonatal and juvenile growth in rats.

Methods. Pregnant rats were divided into five groups designated as: 1) control; 2) propylthiouracil (PTU); 3) PTU-NS100; 4) PTU-NS200, and 5) PTU-NS400. All mothers except the control group received 0.005% PTU in their drinking water during lactation. Besides PTU, mothers in groups 3-5 received 100, 200, and 400 mg/kg of NS extract. After lactation period, the off spring continued to receive the same experimental treatment for the first 8 weeks of their life. Ten male off springs of each group were randomly selected, blood samples collected, and the kidney tissues removed.

Results. The serum thyroxin concentration in PTU group was lower than control group and improved by extract. PTU increased the renal malondialdehyde (MDA), while reduced the total thiols concentrations and catalase (CAT) and superoxide dismutase (SOD) activity compared to control group. Administration of 200 and 400 mg/kg of NS extract decreased MDA level, while it increased the total thiols and 400 mg/kg increased CAT and SOD activity in renal tissues compared to PTU group. Serum creatinine and blood urea nitrogen (BUN) in PTU group was higher than in comparison with the control group. 400 mg/kg decreased creatinine, but both 200 and 400 mg/kg improved BUN concentration compared to PTU group.

Conclusion. The results of this study demonstrate that the hydroalcoholic extract of NS has a protective effect on the renal tissue oxidative damage associated with PTU-induced hypothyroidism during neonatal and juvenile growth in rats.

Open access
Central and peripheral control of food intake

Abstract

The maintenance of the body weight at a stable level is a major determinant in keeping the higher animals and mammals survive. Th e body weight depends on the balance between the energy intake and energy expenditure. Increased food intake over the energy expenditure of prolonged time period results in an obesity. Th e obesity has become an important worldwide health problem, even at low levels. The obesity has an evil effect on the health and is associated with a shorter life expectancy. A complex of central and peripheral physiological signals is involved in the control of the food intake. Centrally, the food intake is controlled by the hypothalamus, the brainstem, and endocannabinoids and peripherally by the satiety and adiposity signals. Comprehension of the signals that control food intake and energy balance may open a new therapeutic approaches directed against the obesity and its associated complications, as is the insulin resistance and others. In conclusion, the present review summarizes the current knowledge about the complex system of the peripheral and central regulatory mechanisms of food intake and their potential therapeutic implications in the treatment of obesity.

Open access
Eff ects of hemin, a heme oxygenase-1 inducer in L-arginine-induced acute pancreatitis and associated lung injury in adult male albino rats

Abstract

Objective. The aim of the current study was to assess the protective outcome of hemin, a heme oxygenase-1 (HO-1) inducer on L-arginine-induced acute pancreatitis in rats. Acute pancreatitis (AP) is considered to be a critical inflammatory disorder with a major impact on the patient health. Various theories have been recommended regarding the pathophysiology of AP and associated pulmonary complications.

Methods. Twenty-four adult male albino rats were randomly divided into four groups: control group, acute pancreatitis (AP), hemin pre-treated AP group, and hemin post-treated AP group.

Results. Administration of hemin before induction of AP significantly attenuated the L-arginine- induced pancreatitis and associated pulmonary complications characterized by the increasing serum levels of amylase, lipase, tumor necrosis factor-α, nitric oxide, and histo-architectural changes in pancreas and lungs as compared to control group. Additionally, pre-treatment with hemin significantly compensated the deficits in total antioxidant capacities and lowered the elevated malondialdehyde levels observed with AP. On the other hand, post-hemin administration did not show any protection against L-arginine-induced AP.

Conclusions. The current study indicates that the induction of HO-1 by hemin pre-treatment significantly ameliorated the L-arginine-induced pancreatitis and associated pulmonary complications may be due to its anti-inflammatory and antioxidant properties.

Open access
Factors associated with increased irisin levels in the type 1 diabetes mellitus

Abstract

Objective. The aim of the present study was to determine the irisin levels in patients with the type 1 diabetes mellitus (T1DM) and to examine the relation of irisin levels with the inflammation and autoimmunity.

Methods. This study included 35 cases diagnosed with T1DM and 36 healthy volunteers. Antiglutamic acid decarboxylase (anti-GAD), islet cell antibody (ICA), and insulin autoantibody levels were measured in patients at the time when they were included into the study and recorded from the patient files. Serum irisin levels were measured by ELISA kit.

Results. The median irisin levels were determined higher in T1DM group compared to the control one (6.8 ng/ml vs. 4.8 ng/ml, p=0.022; respectively). Median irisin levels were higher in anti-GAD (p=0.022) and ICA (p=0.044) positive groups compared to negative groups. In T1DM group, irisin levels displayed positive correlation with glycosylated hemoglobin (HbA1c) (r=0.377, p<0.001) and anti-GAD (r=0.392, p=0.020) and negative correlation with creatinine (r=-0390, p=0.021). In multivariate regression model, HbA1c (B±SE: 2.76±17683, p<0.001), and anti-GAD (B±SE: 2.311±0.610, p=0.001) were determined as independent predictors for predicting the irisin levels.

Conclusion. In patients with T1DM, which chronic inflammation and autoimmunity take part in their etiopathogenesis, anti-GAD levels were an independent risk factor for the irisin. Th is may suggest that factors such as inflammation and autoimmunity can be effective in the synthesis of irisin.

Open access
Hypoxic regulation of the expression of genes encoded estrogen related proteins in U87 glioma cells: eff ect of IRE1 inhibition

Abstract

Objective. The aim of the present study was to examine the effect of inhibition of endoplasmic reticulum stress signaling, mediated by IRE1 (inositol requiring enzyme 1), which is a central mediator of the unfolded protein response on the expression of genes encoded estrogen related proteins (NRIP1/RIP140, TRIM16/EBBP, ESRRA/NR3B1, FAM162A/E2IG5, PGRMC2/PMBP, and SLC39A6/LIV-1) and their hypoxic regulation in U87 glioma cells for evaluation of their possible significance in the control of glioma cells proliferation.

Methods. The expression of NRIP1, EBBP, ESRRA, E2IG5, PGRMC2, and SLC39A6 genes in U87 glioma cells, transfected by empty vector pcDNA3.1 (control) and cells without IRE1 signaling enzyme function (transfected by dnIRE1) upon hypoxia, was studied by a quantitative polymerase chain reaction.

Results. Inhibition of both enzymatic activities (kinase and endoribonuclease) of IRE1 signaling enzyme function up-regulates the expression of EBBP, E2IG5, PGRMC2, and SLC39A6 genes is in U87 glioma cells in comparison with the control glioma cells, with more significant changes for E2IG5 and PGRMC2 genes. At the same time, the expression of NRIP1 and ESRRA genes is strongly down-regulated in glioma cells upon inhibition of IRE1. We also showed that hypoxia increases the expression of E2IG5, PGRMC2, and EBBP genes and decreases NRIP1 and ESRRA genes expression in control glioma cells. Furthermore, the inhibition of IRE1 in U87 glioma cells decreases the eff ect of hypoxia on the expression of E2IG5 and PGRMC2 genes, eliminates hypoxic regulation of NRIP1 gene, and enhances the sensitivity of ESRRA gene to hypoxic condition. Furthermore, the expression of SLC39A6 gene is resistant to hypoxia in both the glioma cells with and without IRE1 signaling enzyme function.

Conclusions. Results of this investigation demonstrate that inhibition of IRE1 signaling enzyme function affects the expression of NRIP1, EBBP, ESRRA, E2IG5, PGRMC2, and SLC39A6 genes in U87 glioma cells in gene specific manner and these changes possibly contribute to the suppression of the cell proliferation. Most of these genes are regulated by hypoxia and preferentially through IRE1 signaling pathway of endoplasmic reticulum stress.

Open access
Intense blue light therapy during the night-time does not suppress the rhythmic melatonin biosynthesis in a young boy

Abstract

Objective. Melatonin is a hormone predominantly synthesized and secreted during the night by the pineal gland. Artificial light at night, especially its blue part, acutely suppresses the melatonin production. Th e aim of the present study was to find out, whether an intense blue light phototherapy of severe hyperbilirubinemia, may suppress the melatonin production during the night when the eyes will be properly protected by a sleep mask.

Methods. The main melatonin metabolite, 6-sulphatoxymelatonin was measured in urine in a nine-year old boy suffering from the Crigler-Najjar syndrome type I. The boy was treated during the sleep period with an intense blue light (to 1800 lx) 10 h/day, since his birth. During the phototherapy, his eyes were protected with a sleep mask. The concentration of 6-sulphatoxymelatonin was determined in the first morning urine and urine collected afternoon during the six days. The patient was exposed to phototherapy for three nights, two nights without and the last one with the treatment. The control urine samples were obtained from 8 healthy nine-year old boys. The level of 6-sulphatoxymelatonin was measured by radioimmunoassay and the data were normalized to urinary creatinine.

Results. A distinct melatonin production rhythm was found and 6-sulphatoxymelatonin concentration in urine of the patient was comparable with the values obtained by the control group. No differences in 6-sulphatoxymelatonin levels were found between the nights with and without the phototherapy applied.

Conclusions. We conclude that the whole night treatment of hyperbilirubinemia with intense blue light has negligible side effect on the rhythmic melatonin production, when the eyes are sufficiently protected by the sleep mask.

Open access