Selenium in Sepsis A new magic bullet? Daren K. Heyland, MD, FRCPC, MSc Professor of Medicine, Queen’s University, Kingston, Ontario

 Updated January 2009  Summarizes 207 trials studying >20,000 patients  34 topics 17 recommendations

Background Essential trace element for all mammalian species Involved in a number of physiological processes Incorporated into 25 different selenoproteins with activity related to –T cell immunity –Modulate inflammation –Prevent lipid peroxidation –Thyroid metabolism Deficiencies lead to submaximal expression of GSH- Px and other selenoproteins compromising cell function Selenium

Background Current dietary recommendations is between ug/day (based on optimize G-Px) Found in various foods such as meats, nuts, breads, etc but is largely a function of soil composition. Some geographic areas are Selenium –poor (china, parts of US and Europe) Selenium

In Critical Illness, Low Levels of Se related to Severity of Illness Manzanares ICM 2009;35:882

In Critical Illness, Low Levels of Se related to Severity of Illness Manzanares ICM 2009;35:882 Healthy Controls ICU Patients ICU +SIRS ICU +MODS

…and Correlate with GPx activity Manzanares ICM 2009;35:882

OFR CONSUMPTION OFR PRODUCTION Depletion of Antioxidant Enzymes OFR Scavengers Vitamins/Cofactors Infection Inflammation Ischemia OFR production > OFR consumption = Impaired - organ function - immune function - mtiochondrial function Complications and Death OXIDATIVE STRESS Rationale for Antioxidants

Endogenous antioxidant defense mechanisms Enzymes (superoxide dismutase, catalase, glutathione perioxidase, glutathione reductase including their cofactors Zn and Selenium) Sulfhydryl group donors (glutathione) Vitamins E, C, and B-carotene Rationale for Antioxidants Low endogenous levels  Lipid peroxidation and inflammation  Organ failure  Mortality

Oxidative Stress Connected to Organ Failure Motoyama Crit Care Med 2003;31:1048

Non-survivors associated with : –Higher APACHE III scores –Higher degree of oxidative stress LPP SH TAC –Higher levels of inflammation (NOx) –Higher levels of leukocyte activation (myeloperoxidase, PMN elastase) Rationale for Antioxidants Alonso de Vega CCM 2002; 30: 1782

21 patients with septic shock Exposed plasma from patients to naïve human umbilical vein endothelial cells and quantified degree of oxidative stress by a fluorescent probe (2,7,- dichorodihydrofluorescien diacetate) Rationale for Antioxidants Huet CCM 2007; 35: 821

Rationale for Antioxidants Huet CCM 2007; 35: 821

Death Metabolic Shutdown Survivors ↓mt DNA ↓ ATP, ADP, NADPH ↓ Resp chain activity Ultra structural changes ↓ mitochondrial activity Prolonged inflammation NO Endocrine effects cytokine effect Genetic down regulation Tissue hypoxia preserved ATP Recovery of mt DNA Regeneration of mito proteins Rationale for Antioxidants

Heyland JPEN 2007;31:109

Mitochondrial Dysfunction is a Time- Dependent Phenonmenon Hypoxia Accelerates Nitric Oxide Inhibition of Complex 1 Activity Nitration of Complex 1 in Macrophages activated with LPS and IFN 21% O2 1% O2 Frost Am J Physio Regul Interg Comp Physio 2005;288:394

mitochondria Cell Respiratory chain nucleus nDNA mtDNA Mitochondrial Damage ROS RNS LPS exposure leads to GSH depletion and oxidation of mtDNA within 6-24 hours Levy Shock 2004;21:110 Suliman CV research 2004;279 Potentially Irreversible by 48 hours

Effect of Antioxidants on Mitochondrial Function Heyland JPEN 2007;31:109

Smallest Randomized Trial of Selenium in Sepsis  Single center RCT  double-blinded  ITT analysis  40 patients with severe sepsis  Mean APACHE II 18  Primary endpoint: need for RRT  standard nutrition plus 474 ug x 3 days, 316 ug x 3 days; 31.6 ug thereafter vs 31.6 ug/day in control Mishra Clinical Nutrition 2007;26:41-50

Smallest Randomized Trial of Selenium in Sepsis Increased selenium levels Increased GSH-Px activity No difference in RRT (5 vs 7 patients) mortality (44% vs 50%) Other clinical outcomes Mishra Clinical Nutrition 2007;26:41-50 *p=<0.006 * * Effect on SOFA scores

Randomized, Prospective Trial of Antioxidant Supplementation in Critically Ill Surgical Patients Nathens Ann Surg 2002;236:814  Surgical ICU patients, mostly trauma  770 randomized; 595 analysed  alpha-tocopherol 1,000 IU (20 mL) q8h per naso- or orogastric tube and 1,000 mg ascorbic acid IV q8h or placebo  Tendency to less pulmonary morbidity and shorter duration of vent days

Influence of early antioxidant supplements on clinical evolution and organ function in critically ill cardiac surgery, major trauma and subarachnoid hemorrhage patients. CRP levels daily in the Control groups Significant reduction with AOX in Cardiac and Trauma but not SAH Berger Crit Care 2008  RCT  200 patients  IV supplements for 5 days after admission (Se 270 mcg, Zn 30 mg, Vit C 1.1 g, Vit B1 100 mg) with a double loading dose on days 1 and 2 (AOX group), or placebo.  No affect on clinical outcomes

Largest Randomized Trial of Antioxidants  Multicenter RCT in Germany  double-blinded  non-ITT analysis  249 patients with severe sepsis  standard nutrition plus 1000 ug bolus followed by 1000 ug/day or placebo x14 days Greater treatment effect observed in those patients with: supra normal levels vs normal levels of selenium Higher APACHE III More than 3 organ failures Crit Care Med 2007;135:1 p=0.11

o16 RCTs oSingle nutrients (selenium) and combination strategies (selenium, copper, zinc, Vit A, C, & E, and NAC) oAdministered various routes (IV/parenteral, enteral and oral) oPatients: oCritically ill surgical, trauma, head injured oSIRS, Pancreatitis, Pancreatic necrosis oBurns oMedical oSepsis, Septic Shock Supplementation with Antioxidants in the Critically Ill: A meta-analysis Heyland Int Care Med 2005:31;327;updated on

Effect of Combined Antioxidant Strategies in the Critically Ill Effect on Mortality Updated Jan 2009, see

Effect of Selenium-based Strategies in the Critically Ill Effect on Mortality Updated Jan 2009, see

Biological Plausibility! Inflammation/oxidative stressMitochondrial dysfunctionOrgan dysfunction Antioxidants

Most Recent Trial of Selenium Supplementation in Sepsis Anti-inflammatory, anti-apoptotic effects of high dose Se Pilot RCT, double-blind, placebo controlled 60 patients with severe septic shock Forceville Crit Care 2007:11:R mcg followed by 1000mcg/day x 10 days Placebo No difference in pressor withdrawl, LOS, mortality New organ failure: 32 vs 14%, p=0.09

Toxicity dependent on dose and type of selenium

REducing Deaths from OXidative Stress: The REDOXS study A multicenter randomized trial of glutamine and antioxidant supplementation in critical illness

The Research Protocol In enterally fed, critically ill patients with a clinical evidence of acute multi organ dysfunction –What is the effect of glutamine supplementation compared to placebo –What is the effect of antioxidant supplementation compared to placebo …on 28 day mortality? The Question(s)

1200 ICU patients Evidence of organ failure R glutamine placebo Concealed Stratified by  site R R antioxidants placebo Factorial 2x2 design placebo antioxidants  Shock REducing Deaths from OXidative Stress: The REDOXS study

GroupEnteral Supplement Parenteral Supplement ( Glutamine AOX) (Glutamine AOX) AGlutamine + AOX+Glutamine + Selenium BPlacebo + AOX+Placebo + Selenium CGlutamine + Placebo+Glutamine + Placebo DPlacebo + Placebo+Placebo + Placebo Combined Entered and Parental Nutrients

Optimal Dose? High vs Low dose: –observations of meta-analysis Providing experimental nutrients in addition to standard enteral diets

Optimizing the Dose of Glutamine Dipeptides and Antioxidants in Critically ill Patients: A phase 1 dose finding study of glutamine and antioxidant supplementation in critical illness JPEN 2007;31:109

The Research Protocol In critically ill patients with a clinical evidence of hypoperfusion... What is the maximal tolerable dose (MTD) of glutamine dipeptides and antioxidants as judged by its effect on multiorgan dysfunction? The Question

The Research Protocol Single Center Open-label Dose-ranging study Prospective controls The Design Critically Ill patients in shock Patients

The Research Protocol Intervention Group NDose of Dipeptides (glutamine) Parenterally* (gm/kg/day) Enterally^ (gm/day) AOX (.35) (15)½ can 47.5 (.35)42 (30) full can (300 mcg EN Selenium) 57.5 (.35)42 (30) full can + 500ug IV Selenium

The Research Protocol Outcomes Primary: ∆SOFA Secondary (groups 2-5); Plasma levels of Se, Zn, and vitamins TBARS Glutathione Mitochondrial function (ratio)

Control N = 30 Group 2 N =7 Group 3 N= 7 Group 4 N= 7 Group 5 N=7 All N=58 Age (Mean) Female (%)11 (37%)2(29%)1(14%)2(29%)3(43%)19(33%) APACHE II score (Mean) Etiology of shock Cardiogenic (%) Septic (%) Hypovolemic (%) 6 (86%) 1(14%) 3 (43%) 4 (57%) 3 (43%) 4 (57%) 1(14%) 5(71%) 1(14%) 13(46%) 14(50%) 1(4%) ICU days (Median) day mortality (%)9(30%)3(43%)2(29%)3(43%)1(14%)18(31%) Baseline Characteristics

4 vs 5: p=0.17 Effect on SOFA

Effect on TBARS

Effect on Glutathione

Effect on MITO RATIO

Inferences High dose appears safe High dose associated with –no worsening of SOFA Scores –greater resolution of oxidative stress –greater preservation of glutathione –Improved mitochondrial function Heyland JPEN Mar 2007 ParenterallyEnterally Glutamine/day0.35 gms/kg30 gms Antioxidants per day 500 mcg Selenium Vit C 1500 mg Vit E 500 mg B carotene 10 mg Zinc 20 mg Se 300 ug

REDOXS: A new paradigm! Nutrients dissociated from nutrition Focus on single nutrient administration Rigorous, large scale, multicenter trial of nutrition related intervention powered to look at mortality sick homogenous population Preceded by: –standardization of nutrition support thru the development and implementation of CPGs –a dosing optimizing study Funded by CIHR

Conclusions “Insufficient data to put forward a recommendation for Selenium alone” “Based on 3 level 1 and 13 level 2 studies, the use of supplemental combined vitamins and trace elements should be considered in critically ill patients.” Canadian CPGs Optimal Dose: (800) mcg/day