Search results for "CYSTEINE"

Structure, mechanism and regulation of peroxiredoxins.

2003

Peroxiredoxins (Prxs) are a ubiquitous family of antioxidant enzymes that also control cytokine-induced peroxide levels which mediate signal transduction in mammalian cells. Prxs can be regulated by changes to phosphorylation, redox and possibly oligomerization states. Prxs are divided into three classes: typical 2-Cys Prxs; atypical 2-Cys Prxs; and 1-Cys Prxs. All Prxs share the same basic catalytic mechanism, in which an active-site cysteine (the peroxidatic cysteine) is oxidized to a sulfenic acid by the peroxide substrate. The recycling of the sulfenic acid back to a thiol is what distinguishes the three enzyme classes. Using crystal structures, a detailed catalytic cycle has been deriv…

Influence of N-acetylcysteine on hepatic amino acid metabolism in patients undergoing orthotopic liver transplantation

2001

Experimental treatment with the antioxidant and glutathione precursor N-acetylcysteine (NAC) has been performed in orthotopic liver transplantation (OLT) to reduce reperfusion injury. To investigate the effect of NAC on the hepatic and intestinal amino acid metabolism, intraoperative amino acid exchange rates were studied in liver transplant recipients with high dose NAC treatment (n = 10) and in control patients (n = 9). Treatment with NAC was found to cause a loss of amino acids and increased urea nitrogen release from the liver graft. The net balance of most amino acids was shifted to increased hepatic release or decreased hepatic uptake. The initial cumulative splanchnic release of all …

Effects of verapamil and N-acetylcysteine on doxorubicin or isoproterenol cardiotoxicity in mice

1989

Nostotrebin 6 Related Cyclopentenediones and δ-Lactones with Broad Activity Spectrum Isolated from the Cultivation Medium of the Cyanobacterium Nosto…

2020

Cyanobacteria are an interesting source of biologically active natural products, especially chemically diverse and potent protease inhibitors. On our search for inhibitors of the trypanosomal cysteine protease rhodesain, we identified the homodimeric cyclopentenedione (CPD) nostotrebin 6 (1) and new related monomeric, dimeric, and higher oligomeric compounds as the active substances in the medium extract of Nostoc sp. CBT1153. The oligomeric compounds are composed of two core monomeric structures, a trisubstituted CPD or a trisubstituted unsaturated δ-lactone. Nostotrebin 6 thus far has been the only known cyanobacterial CPD. It has been found to be active in a broad variety of assays, indi…

Screening of cyanobacteria extracts for inhibitory activity against the cysteine protease rhodesain of Trypanosoma brucei

2016

Eight-week consumption of milk enriched with omega 3 fatty acids raises their blood concentrations yet does not affect lipids and cardiovascular dise…

2014

Adequate concentrations of omega 3 fatty acids (FA) may be maintained by consuming foods naturally rich in or functional foods enriched with those essential FA. We assessed the effects of an 8-week consumption of milk enriched with 400. mg of omega 3 FA on blood lipid levels and selected cardiovascular risk factors in adult healthy volunteers. Participants (n= 157) were randomized to consume - for eight weeks - either 500. mL/day of 1% fat milk providing 150. mg of eicosapentaenoic (EPA), 150. mg of docosahexaenoic (DHA), and 100. mg of α-linolenic (ALA) acids or 500. mL/day of non-enriched 1% fat milk. At week 8, we observed significant increments of blood EPA and DHA in the intervention g…

N-Acetylcysteine for the Management of Non-Acetaminophen Drug-Induced Liver Injury in Adults: A Systematic Review

2022

Introduction: Idiosyncratic drug-induced liver injury (DILI) is a rare adverse reaction to drugs and other xenobiotics. DILI has different grades of severity and may lead to acute liver failure (ALF), for which there is no effective therapy. N-acetylcysteine (NAC) has been occasionally tested for the treatment of non-acetaminophen drug-induced ALF. However, limited evidence for its efficacy and safety is currently available. Our aim was to elucidate the benefit and safety of NAC in DILI and evaluate its hepatoprotective effect.Methods: We conducted a systematic review to evaluate the management and prevention focused on NAC in idiosyncratic DILI. The main outcomes included mortality due to …

Novel cleavable cell-penetrating peptide-drug conjugates: synthesis and characterization

2014

We report the first drug conjugate with a negatively charged amphipathic cell-penetrating peptide. Furthermore, we compare two different doxorubicin cell-penetrating peptide conjugates, which are both unique in their properties, due to their net charge at physiological pH, namely the positively charged octaarginine and the negatively charged proline-rich amphipathic peptide. These conjugates were prepared exploiting a novel heterobifunctional crosslinker to join the N-terminal cysteine residue of the peptides with the aliphatic ketone of doxorubicin. This small linker contains an activated thiol as well as aminooxy functionality, capable of generating a stable oxime bond with the C-13 carbo…

Relationship Between Homocysteine Serum Level and Other Blood Analyses Parameters in HIV-infected Patients

2011

N-Acetylcysteine for Preventing Acetaminophen-Induced Liver Injury: A Comprehensive Review.

2022

Aims: N-Acetylcysteine (NAC) is used as an antidote in acetaminophen (APAP) overdose to prevent and mitigate drug-induced liver injury (DILI). Our objective was to systematically review evidence of the use of NAC as a therapeutic option for APAP overdose and APAP-related DILI in order to define the optimal treatment schedule and timing to start treatment.Methods: Bibliographic databases (PubMed, Web of Science, Embase, and MEDLINE) were searched for retrospective and prospective cohort studies, case series, and clinical trials. The prespecified primary outcomes were DILI-related mortality, hepatotoxicity, and adverse events (AEs).Results: In total, 34 studies of NAC usage in APAP-related DI…