Selenium Exposure and Cancer Risk: an Updated Meta-analysis and Meta-regression

Serum Concentrations of 15 Elements Among Helicobacter Pylori-Infected Residents from Lujiang County with High Gastric Cancer Risk in Eastern China

Helicobacter pylori (H. pylori) infection can interfere with the absorption of most elements, and the variations of some element levels are related to the incidence of gastric cancer. However, there have been conflicting results concerning the influence of H. pylori infection on serum element levels. The present study aimed to compare the serum element concentrations of H. pylori-infected local residents with uninfected residents from Lujiang County with high gastric cancer risk in Eastern China. We used data and serum samples from the H. pylori screening-survey program which was a cross-sectional study. We took 155 samples randomly from the screening survey, identified 74 H. pylori-positive residents and 81 H. pylori-negative residents by a serological test. The serum concentrations of 15 elements (calcium, magnesium, iron, zinc, selenium, copper, molybdenum, chromium, cobalt, nickel, lead, cadmium, mercury, arsenic, and aluminum) were determined using inductively coupled plasma mass spectrometry. Serum cobalt was found at higher levels in the H. pylori-infected residents than the H. pylori-uninfected residents (0.246 vs 0.205 μg/L, P = 0.022), but no statistically significant differences in the serum levels of other elements were found. This is the first study to report the serum concentrations of 15 elements and their relationships with the infection status of H. pylori among local residents from Lujiang County with high gastric cancer risk. Although the International Agency for Research on Cancer has classified cobalt and other soluble cobalt salts as possibly carcinogenic to human beings, our results may provide a clue to the relationships between cobalt, H. pylori, and gastric cancer.

Selenium Analysis and Speciation in Dietary Supplements Based on Next-Generation Selenium Ingredients

Selenium is essential for humans and the deficit of Se requires supplementation. In addition to traditional forms such as Se salts, amino acids, or selenium-enriched yeast supplements, next-generation selenium supplements, with lower risk for excess supplementation, are emerging. These are based on selenium forms with lower toxicity, higher bioavailability, and controlled release, such as zerovalent selenium nanoparticles (SeNPs) and selenized polysaccharides (SPs). This article aims to focus on the existing analytical systems for the next-generation Se dietary supplement, providing, at the same time, an overview of the analytical methods available for the traditional forms. The next-generation dietary supplements are evaluated in comparison with the conventional/traditional ones, as well as the analysis and speciation methods that are suitable to reveal which Se forms and species are present in a dietary supplement. Knowledge gaps and further research potential in this field are highlighted. The review indicates that the methods of analysis of next-generation selenium supplements should include a step related to chemical species separation. Such a step would allow a proper characterization of the selenium forms/species, including molecular mass/dimension, and substantiates the marketing claims related to the main advantages of these new selenium ingredients.

Opposite Regulation of CHOP and GRP78 and Synergistic Apoptosis Induction by Selenium Yeast and Fish Oil via AMPK Activation in Lung Adenocarcinoma Cells

Selenium has been intensively studied for the use of cancer prevention and treatment. However, the clinical effects are still plausible. To enhance its efficacy, a combinational study of selenium yeast (SY) and fish oil (FO) was performed in A549, CL1-0, H1299, HCC827 lung adenocarcinoma (LADC) cells to investigate the enhancement in apoptosis induction and underlying mechanism. By sulforhodamine B staining, Western blot and flow cytometric assays, we found a synergism between SY and FO in growth inhibition and apoptosis induction of LADC cells. In contrast, the fetal lung fibroblast cells (MRC-5) were unsusceptible to this combination effect. FO synergized SY-induced apoptosis of A549 cells, accompanied with synergistic activation of AMP-activated protein kinase (AMPK) and reduction of Cyclooxygenase (COX)-2 and β-catenin. Particularly, combining with FO not only enhanced the SY-elevated proapoptotic endoplasmic reticulum (ER) stress marker CCAAT/enhancer-binding protein homologous protein (CHOP), but also reduced the cytoprotective glucose regulated protein of molecular weight 78 kDa (GRP78). Consequently, the CHOP downstream targets such as phospho-JNK and death receptor 5 were also elevated, along with the cleavage of caspase-8, -3, and the ER stress-related caspase-4. Accordingly, inhibition of AMPK by compound C diminished the synergistic apoptosis induction, and elevated CHOP/GRP78 ratio by SY combined with FO. The AMPK-dependent synergism suggests the combination of SY and FO for chemoprevention and integrative treatment of LADC.

Prostate cancer chemoprevention by natural agents: Clinical evidence and potential implications

Prostate cancer (PCa) is the most common non-skin cancer and the second leading cause of cancer-related deaths in American men. Due to its long latency period, PCa is considered as an ideal cancer type for chemopreventive interventions. Chemopreventive agents include various natural or synthetic agents that prevent or delay cancer development, progression and/or recurrence. Pre-clinical studies suggest that many natural products and dietary agents have chemopreventive properties. However, a limited number of these agents have been tested in clinical trials, with varying success. In this review, we have discussed the available clinical studies regarding the efficacy of natural chemopreventive agents against PCa, including tea polyphenols, selenium, soy proteins, vitamins and resveratrol. We have also provided a discussion on the clinical challenges and opportunities for the potential use of chemopreventive agents against PCa. Based on available literature, it appears that the variable outcomes of the chemopreventive clinical studies necessitate a need for additional studies with more rigorous designs and methodical interpretations in order to measure the potential of the natural agents against PCa.

A short-term intervention with selenium affects expression of genes implicated in the epithelial-to-mesenchymal transition in the prostate

In parallel with the inconsistency in observational studies and chemoprevention trials, the mechanisms by which selenium affects prostate cancer risk have not been elucidated. We conducted a randomized, placebo-controlled trial to examine the effects of a short-term intervention with selenium on gene expression in non-malignant prostate tissue. Twenty-three men received 300 μg selenium per day in the form of selenized yeast (n=12) or a placebo (n=11) during 5 weeks. Prostate biopsies collected from the transition zone before and after intervention were analysed for 15 participants (n=8 selenium, n=7 placebo). Pathway analyses revealed that the intervention with selenium was associated with down-regulated expression of genes involved in cellular migration, invasion, remodeling and immune responses. Specifically, expression of well-established epithelial markers, such as E-cadherin and epithelial cell adhesion molecule EPCAM, was up-regulated, while the mesenchymal markers vimentin and fibronectin were down-regulated after intervention with selenium. This implies an inhibitory effect of selenium on the epithelial-to-mesenchymal transition (EMT). Moreover, selenium was associated with down-regulated expression of genes involved in wound healing and inflammation; processes which are both related to EMT. In conclusion, our explorative data showed that selenium affected expression of genes implicated in EMT in the transition zone of the prostate.

The risk of cognitive impairment associated with hearing function in older adults: a pooled analysis of data from eleven studies

Impaired hearing and cognition are disabling conditions among older adults. Research has presented inconsistent conclusions regarding hearing impairment posing a risk for cognitive impairment. We aimed to assess this from published evidence via searching PubMed and Embase, from the inception of the databases indexed to December 2, 2016. For those high-quality studies retrieved, relative risk (RR) and 95% confidence intervals (CIs) were combined to estimate the risk of cognitive impairment. Eleven cohort studies were included in the present study. Pooled results found that elderly people with disabled peripheral and central hearing function had a higher risk of cognitive impairment (for moderate/severe peripheral hearing impairment: RR = 1.29, 95% CI: 1.04-1.59 during a follow-up ≤6 years. RR = 1.57, 95% CI: 1.13-2.20 during a follow-up >6 years; for severe central hearing impairment, RR = 3.21, 95% CI: 1.19-8.69) compared to those with normal hearing function. We also recorded a dose-response trend for cognitive impairment as hearing thresholds rose. No evident bias from potential confounding factors was found with one exception: the length for clinical follow-up. Although results are preliminary because qualifying studies were few, statistical findings were consistent with older people identified as having greater levels of hearing loss, having a corresponding higher risk of cognitive impairment.

Epidemiology of Esophageal Squamous Cell Carcinoma

Esophageal squamous cell carcinoma (ESCC) accounts for about 90% of the 456,000 incident esophageal cancers each year. Regions of high incidence include Eastern to Central Asia, along the Rift Valley in East Africa, and into South Africa. There are many causes of ESCC, which vary among regions. Early studies in France associated smoking cigarettes and heavy alcohol consumption with high rates of ESCC, but these factors cannot explain the high incidence in other regions. We discuss other risk factors for ESCC, including polycyclic aromatic hydrocarbons from a variety of sources, high-temperature foods, diet, and oral health and the microbiome-all require further research. A growing list of defined genomic regions affects susceptibility, but large genome-wide association studies have been conducted with ethnic Chinese subjects only; more studies are called for in the rest of Asia and Africa. ESCC has been understudied, but growing infrastructure in more high-incidence countries will allow rapid progress in our understanding.

Serum Selenium Levels and Cervical Cancer: Systematic Review and Meta-Analysis

Several studies have investigated the relationship between serum Se concentration and cervical cancer, but the results were inconsistent. Thus, we conducted a systematic review and meta-analysis to evaluate the association between serum selenium levels and cervical cancer. Twelve studies investigating the association by univariate analysis and five studies by multivariate analysis were identified after a systematic search of PubMed, Wanfang, CNKI, and SinoMed databases. Standard mean differences (SMD) or odds ratios (OR) with the corresponding 95% confidence intervals (CI) were pooled to compare the selenium levels between different groups. In univariate analysis, serum selenium levels in cervical cancer cases were significantly lower than in controls (SMD = -4.86, 95% CI -6.03-3.69). Subgroup analysis showed consistent results. In multivariate analysis, serum selenium levels in cervical cancer cases were also significantly lower than in controls (OR = 0.55, 95% CI 0.42-0.73). After treatment, the serum selenium levels increased significantly (SMD = 2.59, 95% CI 0.50-4.69). In conclusion, high serum selenium levels were associated with cervical cancer, and selenium exposure might be a protective factor for cervical cancer.

The Regulation of Pathways of Inflammation and Resolution in Immune Cells and Cancer Stem Cells by Selenium

Cancer is a complex disease where cancer stem cells (CSCs) maintain unlimited replicative potential, but evade chemotherapy drugs through cellular quiescence. CSCs are able to give rise to bulk tumor cells that have the capability to override antiproliferative signals and evade apoptosis. Numerous pathways are dysregulated in tumor cells, where increased levels of prooxidant reactive oxygen and nitrogen species can lead to localized inflammation to exacerbate all three stages of tumorigenesis: initiation, progression, and metastasis. Modulation of cellular metabolism in tumor cells as well as immune cells in the tumor microenvironment (TME) can impact inflammatory networks. Altering these pathways can potentially serve as a portal for therapy. It is well known that selenium, through selenoproteins, modulates inflammatory pathways in addition to regulating redox homeostasis in cells. Therefore, selenium has the potential to impact the interaction between tumor cells, CSCs, and immune cells. In the sections later, we review the current status of knowledge regarding this interaction, with reference to leukemia stem cells, and the importance of selenium-dependent regulation of inflammation as a potential mechanism to affect the TME and tumor cell survival.

Methylseleninic Acid Provided at Nutritional Selenium Levels Inhibits Angiogenesis by Down-regulating Integrin β3 Signaling

Targeting angiogenesis has emerged as a promising strategy for cancer treatment. Methylseleninic acid (MSA) is a metabolite of selenium (Se) in animal cells that exhibits anti-oxidative and anti-cancer activities at levels exceeding Se nutritional requirements. However, it remains unclear whether MSA exerts its effects on cancer prevention by influencing angiogenesis within Se nutritional levels. Herein, we demonstrate that MSA inhibited angiogenesis at 2 µM, which falls in the range of moderate Se nutritional status. We found that MSA treatments at 2 µM increased cell adherence, while inhibiting cell migration and tube formation of HUVECs in vitro. Moreover, MSA effectively inhibited the sprouts of mouse aortic rings and neoangiogenesis in chick embryo chorioallantoic membrane. We also found that MSA down-regulated integrin β3 at the levels of mRNA and protein, and disrupted clustering of integrin β3 on the cell surface. Additionally, results showed that MSA inhibited the phosphorylation of AKT, IκBα, and NFκB. Overall, our results suggest that exogenous MSA inhibited angiogenesis at nutritional Se levels not only by down-regulating the expression of integrin β3 but also by disorganizing the clustering of integrin β3, which further inhibited the phosphorylation involving AKT, IκBα, NFκB. These findings provide novel mechanistic insight into the function of MSA for regulating angiogenesis and suggest that MSA could be a potential candidate or adjuvant for anti-tumor therapy in clinical settings.

Fabrication and physicochemical characterization of porous composite microgranules with selenium oxyanions and risedronate sodium for potential applications in bone tumors

Nanocrystalline hydroxyapatite containing selenite ions (SeHA; 9.6 wt.% of selenium) was synthesized using wet method and subject to careful physicochemical analysis by powder X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy, solid-state nuclear magnetic resonance, wavelength dispersive X-ray fluorescence, and inductively coupled plasma optical emission spectrometry. SeHA was then used to develop the selenium-containing hydroxyapatite/alginate (SeHA/ALG) composite granules. Risedronate sodium (RIS) was introduced to the obtained spherical microgranules of a size of about 1.1-1.5 mm in 2 ways: during the granules' preparation (RIS solution added to a suspension of ALG and SeHA), and as a result of SeHA/ALG granules soaking in aqueous RIS solution. The analysis made using ¹³C and ³¹P cross-polarization magic angle spinning nuclear magnetic resonance confirmed the presence of RIS and its interaction with calcium ions. Then, the release of selenium (inductively coupled plasma optical emission spectrometry) and RIS (high-performance liquid chromatography) from microgranules was examined. Moreover, cytotoxicity of fabricated granules was assessed by MTT test. Selenium release was biphasic: the first stage was short and ascribed to a "burst release" probably from a hydrated surface layer of SeHA crystals, while the next stage was significantly longer and ascribed to a sustained release of selenium from the crystals' interior. The study showed that the method of obtaining microgranules containing RIS significantly affects its release profile. Performed cytotoxicity test revealed that fabricated granules had high antitumor activity against osteosarcoma cells. However, because of the "burst release" of selenium during the first 10 h, the granules significantly reduced viability of normal osteoblasts as well.

Phytotherapy and Nutritional Supplements on Breast Cancer

Breast cancer is the most frequent type of nonskin malignancy among women worldwide. In general, conventional cancer treatment options (i.e., surgery, radiotherapy, chemotherapy, biological therapy, and hormone therapy) are not completely effective. Recurrence and other pathologic situations are still an issue in breast cancer patients due to side effects, toxicity of drugs in normal cells, and aggressive behaviour of the tumours. From this point of view, breast cancer therapy and adjuvant methods represent a promising and challenging field for researchers. In the last few years, the use of some types of complementary medicines by women with a history of breast cancer has significantly increased such as phytotherapeutic products and nutritional supplements. Despite this, the use of such approaches in oncologic processes may be problematic and patient's health risks can arise such as interference with the efficacy of standard cancer treatment. The present review gives an overview of the most usual phytotherapeutic products and nutritional supplements with application in breast cancer patients as adjuvant approach. Regardless of the contradictory results of scientific evidence, we demonstrated the need to perform additional investigation, mainly well-designed clinical trials in order to establish correlations and allow for further validated outcomes concerning the efficacy, safety, and clinical evidence-based recommendation of these products.

Selenium and breast cancer risk: A prospective nested case-control study on serum selenium levels, smoking habits and overweight

Previous research has not been conclusive regarding the association between selenium (Se) and breast cancer. This study was conducted to clarify if there is an association between prediagnostic serum Se levels and breast cancer risk. A population based cohort, the Malmö Diet and Cancer Study, was used and linked with the Swedish cancer registry up to 31 December 2013. Our study included 1,186 women with breast cancer and an equal number of controls. Selenium levels were analysed from stored serum samples. The included individuals were divided into quartiles based on Se value and we compared breast cancer cases with controls using logistic regression yielding odds ratios (OR) with 95% confidence intervals. Serum Se was also analysed as a continuous variable regarding breast cancer risk. The analyses were adjusted for established risk factors and stratified on smoking status and body mass index (BMI). When comparing the highest Se quartile with the lowest, the adjusted OR for breast cancer was 0.98 (0.75-1.26). With selenium as a continuous variable the adjusted OR was 1.00 (1.00-1.01) per 10 ng/ml. When comparing the highest with the lowest Se quartile in women with BMI > 25 kg/m² the adjusted OR was 0.77 (0.53-1.14). We conclude that it is unlikely that prediagnostic serum selenium is overall associated with breast cancer risk and no modifying effect from BMI or smoking was seen.

Cadmium, arsenic, selenium and iron- Implications for tumor progression in breast cancer

The aim of this study was to determine Cd (cadmium) and As (arsenic) contents in human breast cancer tissues, investigate their interactions with Se (selenium) and Fe (iron), and assess their further implications for tumor progression. Metal contents were determined in 42 tissue sets (tumor and adjacent tissue) collected from 42 women diagnosed with primary breast cancer. Analytical methods included AAS and ICP-MS techniques. Significantly higher contents of Cd (p=0.0003), Se (p<0.0001) and Fe (p=0.0441) whereas significantly lower content of As (p<0.0001) were observed in tumors as compared to adjacent tissues. There was a significant positive correlation between Cd and As contents in tumor tissue. However, only Cd was significantly associated with histological type of tumor, its size, grading and progesterone receptor status. This study support the role of Cd in breast cancer risk and progression. The possible link between As exposure and breast cancer is still not clear.

Selenium levels in human breast carcinoma tissue are associated with a common polymorphism in the gene for SELENOP (Selenoprotein P)

Selenium supplementation of the diets of rodents has consistently been shown to suppress mammary carcinogenesis and some, albeit not all, human epidemiological studies have indicated an inverse association between selenium and breast cancer risk. In order to better understand the role selenium plays in breast cancer, 30 samples of tumor tissue were obtained from women with breast cancer and analyzed for selenium concentration, the levels of several selenium-containing proteins and the levels of the MnSOD anti-oxidant protein. Polymorphisms within the genes for these same proteins were determined from DNA isolated from the tissue samples. There was a wide range of selenium in these tissues, ranging from 24 to 854ng/gm. The selenium levels in the tissues were correlated to the genotype of the SELENOP selenium carrier protein, but not to other proteins whose levels have been reported to be responsive to selenium availability, including GPX1, SELENOF and SBP1. There was an association between a polymorphism in the gene for MnSOD and the levels of the encoded protein. These studies were the first to examine the relationship between selenium levels, genotypes and protein levels in human tissues. Furthermore, the obtained data provide evidence for the need to obtain data about the effects of selenium in breast cancer by examining samples from that particular tissue type.

Surface decoration of selenium nanoparticles with curcumin induced HepG2 cell apoptosis through ROS mediated p53 and AKT signaling pathways

Curcumin surface decorated selenium nanoparticles (Se@Cur) has been described in this study. The apoptotic signaling pathways triggered by the Se@Cur are p53 and AKT pathways.

Contribution of mammalian selenocysteine-containing proteins to carcinogenesis

Oxidative stress caused by a sharp growth of free radicals in the organism is a major cause underlying the occurrence of all kinds of malignant formations. Selenium is an important essential trace element found in selenoproteins in the form of selenocysteine, an amino acid differing from cysteine for the presence of selenium instead of sulfur and making such proteins highly active. To date the role of selenium has been extensively investigated through studying the functions of selenoproteins in carcinogenesis. Analysis of the obtained results clearly demonstrates that selenoproteins can act as oncosuppressors, but can also, on the contrary, favor the formation of malignant tumors.

Ultrasmall Biocompatible Bi2Se3 Nanodots for Multimodal Imaging-Guided Synergistic Radiophotothermal Therapy against Cancer

Sub-3 nm ultrasmall Bi₂Se₃ nanodots stabilized with bovine serum albumin were successfully synthesized through a reaction of hydroxyethylthioselenide with bismuth chloride in aqueous solution under ambient conditions. These nanodots exhibit a high photothermal conversion efficiency (η = 50.7%) due to their strong broad absorbance in the near-infrared (NIR) window and serve as a nanotheranostic agent for photoacoustic imaging and photothermal cancer therapy. In addition, they also display radioenhancement with a ratio of 6% due to their sensitivity to X-rays, which makes them a potential sensitizer for radiotherapy. These nanodots were also labled with radioactive ^99mTc for quantification of their biodistribution by single-photon-emission computed tomography (SPECT)/computed tomography (CT) imaging. Our work demonstrates the potential of ultrasmall Bi₂Se₃ nanodots in multimodal imaging-guided synergetic radiophotothermal therapy of cancer.

Phase III randomised chemoprevention study with selenium on the recurrence of non-invasive urothelial carcinoma. The SELEnium and BLAdder cancer Trial

BACKGROUND

In Belgium, bladder cancer (BC) is the fifth most common cancer in men. The per-patient lifetime cost is high. Previous epidemiological studies have consistently reported that selenium concentrations were inversely associated with the risk of BC. We therefore hypothesised that selenium may be suitable for chemoprevention of recurrence of BC.

METHOD

The Selenium and Bladder Cancer Trial (SELEBLAT) was an academic phase III placebo-controlled, double-blind, randomised clinical trial designed to determine the effect of selenium on recurrence of non-invasive urothelial carcinoma conducted in 14 Belgian hospitals. Patients were randomly assigned by a computer program to oral selenium yeast 200 μg once a day or placebo for three years, in addition to standard care. All study personnel and participants were blinded to treatment assignment for the duration of the study. All randomised patients were included in the intention to treat (ITT) and safety analyses. Per protocol analyses (PPAs) included all patients in the study three months after start date.

RESULTS

Between September 18, 2009 and April 18, 2013, 151 and 141 patients were randomised in the selenium and placebo group. Patients were followed until December 31, 2015. The ITT analysis resulted in 43 (28%; 95% CI, 0.21-0.35) and 45 (32%; 95% CI, 0.24-0.40) recurrences in the selenium and placebo group. The hazard ratio (HR) was 0.85 (95% CI, 0.56-1.29; p = 0.44) while the HR for the PPA resulted in 42 and 39 (28%; 95% CI, 0.20-0.35) recurrences in the selenium and placebo group (HR = 0.96 [95% CI, 0.62-1.48]; p = 0.93).

CONCLUSION

Selenium supplementation does not lower the probability of recurrence in BC patients.

Effects of Low-dose Selenium on the Inflammatory Response in Coronary Artery Bypass Graft Surgery: A Clinical Trial

Background

Coronary artery bypass graft (CABG) surgery with cardiopulmonary bypass (CPB) triggers an inflammatory reaction, leading to the development of myocardial damage and dysfunction. It is suggested that selenium (Se), an essential trace element, has a protective role against oxidative stress. Decreased intraoperative Se levels might be an independent predictive factor for postoperative multiorgan failure. In spite of its proposed advantages, however, the optimal timing and dosage are not well known.

Objectives

To determine whether 600 µg of intravenous Se administration before induction of anesthesia for CABG surgery could attenuate inflammatory reactions in an Iranian population.

Methods

This randomized triple-blind clinical trial took place in the department of cardiac surgery of an academic hospital affiliated with Guilan University of Medical Sciences (GUMS) from May 2015 to September 2015. Eighty-eight eligible patients scheduled for elective on-pump CABG surgery were divided into two groups using randomized fixed quadripartite blocks. They received either an intravenous bolus of 600 µg Se before induction of anesthesia, or normal saline as a placebo. We had four measurement time-points: just before induction of anesthesia (T0), immediately after the end of CPB (T1), 24 hours after surgery (T2), and 48 hours after surgery (T3). Interleukin 6 (IL-6), tumor necrosis factor-alpha (TNF-α), and C-reactive protein (CRP) serum levels were measured using the enzyme-linked immunosorbent assay (ELISA).

Results

Data from a total of 81 patients were analyzed: group S (n = 41) and group C (n = 40). There was no significant difference between the two groups with regard to baseline characteristics. In both groups, CPB caused markedly increased IL-6, TNF-α, and CRP plasma concentrations compared with baseline (P = 0.0001). However, the pattern of changes was not significantly different between group S (P = 0.068) and group C (P = 0.26). The IL-6 and TNF-α change trends were significant in each group (P=0.0001). However, comparing the two groups showed no significant difference. With regard to IL-6, there was no significant difference between the two groups at the time-points of T1 (P = 0.34), T2 (P = 0.17), and T3 (P = 0.056), and the same was found for TNF-α at T1 (P = 0.34), T2 (P = 0.17), and T3 (P = 0.056). With regard to CRP, the trend of the changes was significant in each group (P = 0.0001). However, comparing two groups showed a borderline significant difference between them at T1 (P = 0.039), but not at T2 (P = 0.075) or T3 (P = 0.11).

Conclusions

This study revealed that the administration of 600 μg of intravenous Se immediately before induction of anesthesia was safe, but when compared to a placebo, no predominant clinical effects or modifications in the systemic inflammatory response induced by on-pump CABG were observed.

Antioxidant trace elements serum levels in long-term parenteral nutrition (PN): Prevalence and infectious risk associated with deficiencies, a retrospective study from a tertiary home-PN center

INTRODUCTION

Antioxidants essential trace elements (TEs), selenium (Se), zinc (Zn) and copper (Cu) are key dietary components and their supplementation in parenteral nutrition (PN) is recommended. However, the frequency of marginal deficiencies and related clinical outcomes remain poorly known in patients receiving long-term PN.

METHODS AND OBJECTIVES

We conducted a retrospective observational study whose aim was to determine in a cohort of patients (n = 73) with chronic intestinal failure (CIF) enrolled in a tertiary home PN center and receiving long-term PN with systematic multi-TE supplementation, the prevalence of low serum TEs levels. The goal was also to assess mid-term incidence of serious infection and its associated factors.

RESULTS

Among the 73 studied patients, 21.9%, 13.9% and 21.1% had low serum Se (<0.9 μmol/l), Cu (<12.7 μmol/l) and Zn (<12.5 μmol/l) levels, respectively. There was no difference between short bowel syndrome (SBS) and non-SBS patients. 30 patients had at least one of the three serum TEs levels under the cut-off values of deficiency. No specific disease and/or underlying intestinal anatomy were associated with low serum TEs concentration. Cumulative incidence rates of serious infection were 11.1% 95CI[5.7-21.0] and 19.5% 95CI[12.0-30.7] at 6 months and 1 year, respectively. Central venous catheter-related bloodstream infection was the most common infection. Low serum Se was independently associated with a higher risk to develop serious infection (HR 2.65 95CI[1.01-6.97]).

CONCLUSION

Low serum TEs concentration is a frequent condition in patients with CIF even with systematic multi-TE supplementations. Se deficiency exposes to a greater risk of serious infection. This suggests that frequent TEs dosage in this population as well as individually tailored supplementation may be beneficial.