ABSTRACT
Low back pain is frequently encountered in hospitals and is a leading cause of disability, often involving costly imaging that exposes a patient to radiation. A retrospective 12-month audit at a South Australian tertiary hospital aimed to evaluate the frequency, modality and appropriateness of imaging in patients with low back pain. Results showed that the general medical unit was unnecessarily ordering imaging in 40% of patients who exhibited no indications warranting such a procedure. A standardised protocol is required to preventing clinicians from requesting imaging solely for the purposes of self-reassurance, patient reassurance or fear of litigation.
Subject(s)
Clinical Audit , Low Back Pain/diagnostic imaging , Magnetic Resonance Imaging , Practice Patterns, Physicians'/statistics & numerical data , Radiation Exposure/prevention & control , Unnecessary Procedures/statistics & numerical data , Aged , Cost-Benefit Analysis , Decision Making , Humans , Low Back Pain/etiology , Low Back Pain/pathology , Magnetic Resonance Imaging/adverse effects , Magnetic Resonance Imaging/economics , Magnetic Resonance Imaging/statistics & numerical data , Middle Aged , Practice Patterns, Physicians'/economics , Radiation Exposure/adverse effects , Retrospective Studies , South Australia/epidemiology , Unnecessary Procedures/economicsABSTRACT
Patulin (PAT), a mycotoxin contaminant of apples and apple products, has been implicated in nephrotoxicity. PAT depletes glutathione (GSH) and elevates reactive oxygen species (ROS). The antioxidant (AO) response is activated by Nuclear erythroid 2-related factor (NRF2) and enhanced by Silent information regulator 3 (SIRT3). The effects of PAT on these molecules have yet to be examined. We investigated the effects of PAT on AO response survival pathways in human embryonic kidney cells (HEK293). PAT cytotoxicity on HEK293 cells was evaluated (MTT assay; 24 h; [0-100 µM]) to determine an IC50. GSH levels were measured using luminometry. Intracellular ROS was evaluated by flow cytometry. Protein expression of Keap1, NRF2, SIRT3 and PGC-1α was quantified by western blotting and gene expression of SOD2, CAT and GPx was evaluated by qPCR. PAT caused a dose dependent decrease in HEK293 cell viability and a significant increase in levels of intracellular ROS (p = 0.0006). A significant increase in protein expression (p = 0.029) was observed. PAT increased gene expression of SOD2 and CAT (p = 0.0043), however, gene expression of GPx was significantly reduced (p = 0.0043). These results show the up-regulation of NRF2 mediated AO mechanisms in response to PAT toxicity.
Subject(s)
Gene Expression Regulation/drug effects , Kidney/drug effects , Mutagens/toxicity , NF-E2-Related Factor 2/agonists , Oxidative Stress/drug effects , Patulin/toxicity , Transcription Factors/agonists , Cell Survival/drug effects , Glutathione/metabolism , HEK293 Cells , Humans , Inhibitory Concentration 50 , Kidney/metabolism , NF-E2-Related Factor 2/genetics , NF-E2-Related Factor 2/metabolism , Oxidation-Reduction , Oxidoreductases/antagonists & inhibitors , Oxidoreductases/chemistry , Oxidoreductases/genetics , Oxidoreductases/metabolism , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha , Reactive Oxygen Species/agonists , Reactive Oxygen Species/metabolism , Sirtuin 3/genetics , Sirtuin 3/metabolism , Transcription Factors/genetics , Transcription Factors/metabolismABSTRACT
Chronic air pollution exposure during pregnancy can cause oxidative stress leading to adverse birth outcomes. The aim of this study was to assess and compare oxidative stress response in peripheral lymphocytes isolated from pregnant women from a highly industrialized locale (south Durban (SD); n = 50) and a control with lower air pollutant levels (north Durban (ND); n = 50). Oxidative stress response was measured by quantifying malondialdehyde (MDA) levels and a SuperArray gene panel. Mitochondrial function (adenosine triphosphate (ATP) levels and mitochondrial depolarization), DNA integrity (comet assay and mitochondrial DNA (mtDNA) viability) and DNA repair (OGG1) were assessed. Antioxidant response was assessed by quantification of glutathione (GSH) and SOD2, nuclear factor erythroid 2-related factor 2 (Nrf2) and uncoupling protein 2 (UCP2) protein and messenger RNA (mRNA) expression. Levels of MDA (p = 0.9), mitochondrial depolarization (p = 0.88), ATP (1.89-fold), SOD2 (1.23-fold) and UCP2 (1.58-fold) gene expression were elevated in the SD group with significantly higher UCP2 protein levels (p = 0.05) and longer comet tail length (p = 0.0004). The expression of Nrf2 protein (p = 0.03) and mRNA levels (-1.37-fold), GSH concentration (p < 0.0001), mtDNA amplification (-2.04-fold) and OGG1 mRNA (-2.78-fold) activity were decreased in the SD group. Of the 84 oxidative stress-related genes evaluated, 26 were differentially regulated. Pregnant women exposed to higher air pollutant levels showed increased markers for oxidative stress and compromised DNA integrity and repair.
