Search results for "Glutathion"

Two amino acid residues determine the low substrate affinity of human cationic amino acid transporter-2A.

2003

Mammalian cationic amino acid transporters (CAT) differ in their substrate affinity and sensitivity to trans-stimulation. The apparent Km values for cationic amino acids and the sensitivity to trans-stimulation of CAT-1, -2B, and -3 are characteristic of system y+. In contrast, CAT-2A exhibits a 10-fold lower substrate affinity and is largely independent of substrate at the trans-side of the membrane. CAT-2A and -2B demonstrate such divergent transport properties, even though their amino acid sequences differ only in a stretch of 42 amino acids. Here, we identify two amino acid residues within this 42-amino acid domain of the human CAT-2A protein that are responsible for the apparent low af…

Disulfide stress: a novel type of oxidative stress in acute pancreatitis.

2013

Glutathione oxidation and protein glutathionylation are considered hallmarks of oxidative stress in cells because they reflect thiol redox status in proteins. Our aims were to analyze the redox status of thiols and to identify mixed disulfides and targets of redox signaling in pancreas in experimental acute pancreatitis as a model of acute inflammation associated with glutathione depletion. Glutathione depletion in pancreas in acute pancreatitis is not associated with any increase in oxidized glutathione levels or protein glutathionylation. Cystine and homocystine levels as well as protein cysteinylation and γ-glutamyl cysteinylation markedly rose in pancreas after induction of pancreatitis…

Definitive host influences the proteomic profile of excretory/secretory products of the trematode Echinostoma caproni

2016

Background Echinostoma caproni is an intestinal trematode extensively used as experimental model for the study of factors that determine the course of intestinal helminth infections, since this markedly depends on the host species. Although the host-dependent mechanisms for either chronic establishment or early parasite rejection have been broadly studied, little is known regarding the parasite response against different host environments. Methods To identify host-dependent differentially expressed proteins, a comparative proteomic analysis of the excretory/secretory products released from E. caproni adults, isolated from hosts displaying different compatibility with this trematode, was per…

Topical treatment with pterostilbene, a natural phytoalexin, effectively protects hairless mice against UVB radiation-induced skin damage and carcino…

2015

Abstract The aim of our study was to investigate in the SKH-1 hairless mouse model the effect of pterostilbene (Pter), a natural dimethoxy analog of resveratrol (Resv), against procarcinogenic ultraviolet B radiation (UVB)-induced skin damage. Pter prevented acute UVB (360 mJ/cm2)-induced increase in skin fold, thickness, and redness, as well as photoaging-associated skin wrinkling and hyperplasia. Pter, but not Resv, effectively prevented chronic UVB (180 mJ/cm2, three doses/week for 6 months)-induced skin carcinogenesis (90% of Pter-treated mice did not develop skin carcinomas, whereas a large number of tumors were observed in all controls). This anticarcinogenic effect was associated wit…

Glutathione deficiency of the lower respiratory tract in patients with idiopathic pulmonary fibrosis.

2002

Idiopathic pulmonary fibrosis (IPF) is a disease of unknown aetiology. Increased oxidant burden and antioxidant, e.g. glutathione (GSH), deficiency in the lower respiratory tract have been thought to play a role in the progression of IPF. Sputum induction is a safe noninvasive tool to study inflammation in the respiratory tract. The aim of the present study was to evaluate the direct measurement of GSH in induced sputum supernatant. Sixteen IPF patients and 15 healthy, nonsmoking subjects underwent sputum induction. Total GSH in sputum, saliva and plasma was measured spectrophotometrically. Sputum GSH was decreased more then four-fold in IPF patients when compared to healthy subjects (mean …

Oxidative Stress and Respiratory System: Pharmacological and Clinical Reappraisal of N-Acetylcysteine

2014

Abstract The large surface area for gas exchange makes the respiratory system particularly susceptible to oxidative stress-mediated injury. Both endogenous and exogenous pro-oxidants (e.g. cigarette smoke) trigger activation of leukocytes and host defenses. These mechanisms interact in a ìmultilevel cycleî responsible for the control of the oxidant/antioxidant homeostasis. Several studies have demonstrated the presence of increased oxidative stress and decreased antioxidants (e.g. reduced glutathione [GSH]) in subjects with chronic obstructive pulmonary disease (COPD), but the contribution of oxidative stress to the pathophysiology of COPD is generally only minimally discussed. The aim of t…

[Methodologic and clinical aspects of the determination of glutathione in induced sputum in bronchopulmonary diseases].

2003

Decreased glutathione and low catalase activity contribute to oxidative stress in children with α-1 antitrypsin deficiency: Table 1

2014

Background Recent investigations in animal models have revealed oxidative stress and oxidative damage in the pathogenesis of alpha-1 antitrypsin deficiency (AATD). However, no data are available on the oxidative stress status and antioxidant enzyme activity in these patients. This study was aimed to analyse the oxidative stress profile and enzymatic antioxidant defence mechanisms in children with AATD. Methods Oxidative stress parameters and the activity of the main antioxidant enzymes were prospectively measured in serum of fifty-one children diagnosed with AATD and thirty-eight control individuals. Results Oxidative stress was increased in the serum of children with intermediate- (MZ; SZ)…

Initial topical cooling followed by backtable Celsior flush perfusion provides excellent early graft function in porcine single lung transplantation …

2013

Topical in situ cooling of the donor lungs is a prerequisite for procurement of non-heart-beating donor lungs and may be of interest for living related lung donation.Twenty-four single lung transplants were performed in 4 groups of Landrace pigs (6 per group). Control LPD, control Celsior and topical cooling in situ, followed by LPD (exLPD) or Celsior (exCel) ex situ flush, were employed. All lungs were perfused antegrade with 1 liter of solution at 4°C. Lungs were stored immersed in preservation solution for 24 hours at 4°C. After transplantation of the left lung, the right recipient bronchus and pulmonary artery were clamped.Four of 6 animals each in the LPD and Celsior groups and all 6 a…

Is the repair of oxidative DNA base modifications inducible by a preceding DNA damage induction?

2007

In mammalian cells, 7,8-dihydro-8-oxoguanine (8-oxoG) and some other oxidative guanine modifications are removed from the DNA by base excision repair, which is initiated by OGG1 protein. We have tested whether this repair is inducible in mouse embryonic fibroblasts (MEFs), MCF-7 breast cancer cells and primary human fibroblasts by a pretreatment with the photosensitizer Ro19-8022 plus light, which generates predominantly 8-oxoG, or with methyl methanesulfonate (MMS), which generates alkylated bases and abasic sites (AP sites). The results indicate that the repair rate of the oxidative guanine modifications induced by the photosensitizer was not increased if a priming dose of the oxidative o…