Effects of long-term vitamin D and n-3 fatty acid supplementation on inflammatory and cardiac biomarkers in patients with type 2 diabetes: secondary analyses from a randomised controlled trial.

AIMS/HYPOTHESIS: Interventions that reduce inflammation may delay progression of microvascular and macrovascular complications in diabetes. We examined the effects of vitamin D3 and/or n-3 fatty acid supplementation vs placebo on 5 year changes in serum inflammatory and cardiac biomarkers in adults with type 2 diabetes. METHODS: This study reports pre-specified secondary outcomes of the Vitamin D and Omega-3 Trial to Prevent and Treat Diabetic Kidney Disease, in which 1312 US adults with type 2 diabetes and without known cardiovascular disease, malignancy, or end-stage kidney disease were randomised using computer-generated random numbers in blocks of eight to vitamin D3 (2000 IU/day) vs placebo and n-3 fatty acids (eicosapentaenoic acid [EPA] and docosahexaenoic acid [DHA]; 1 g/day) vs placebo in a 2 × 2 factorial design. Participants, examiners, and researchers assessing outcomes were blinded to intervention assignment. We measured serum IL-6, high-sensitivity C-reactive protein (hsCRP) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) at baseline and after 2 and 5 years. RESULTS: A total of 333 participants were randomised to vitamin D3 and placebo n-3 fatty acids, 289 to n-3 fatty acids and placebo vitamin D3, 370 to vitamin D3 and n-3 fatty acids, and 320 to 2 placebos; 989 (75%) and 934 (71%) participants returned blood samples at 2 and 5 years, respectively. Participants had a mean age of 67.6 years (46% women). Overall, baseline geometric means of IL-6, hsCRP and NT-proBNP were 1.2 pg/ml, 1.9 mg/l and 262 ng/l, respectively. After 5 years, mean IL-6 and hsCRP remained within 6% of their baseline values while mean NT-proBNP increased by 55% overall. Compared with placebo, participants assigned to vitamin D3 had a 1.24-fold greater increase in NT-proBNP over 5 years (95% CI 1.09, 1.41; p = 0.003), while IL-6 and hsCRP did not have a significant difference in change. Comparing n-3 fatty acids with placebo, there was no significant difference in change in IL-6, hsCRP or NT-proBNP. No heterogeneity was observed in subgroup analyses accounting for baseline eGFR, urine albumin to creatinine ratio, initial biomarker concentration, 25-hydroxyvitamin D level or EPA+DHA index. CONCLUSIONS/INTERPRETATION: Among adults with type 2 diabetes, supplementation with vitamin D3 or n-3 fatty acids did not reduce IL-6, hsCRP or NT-proBNP over 5 years. TRIAL REGISTRATION: ClinicalTrials.gov NCT01684722 FUNDING: The study was funded by grant R01DK088762 from the National Institute of Diabetes and Digestive and Kidney Diseases. Graphical abstract.

Effect of Vitamin D and Omega-3 Fatty Acid Supplementation on Kidney Function in Patients With Type 2 Diabetes: A Randomized Clinical Trial.

Importance: Chronic kidney disease (CKD) is a common complication of type 2 diabetes that can lead to end-stage kidney disease and is associated with high cardiovascular risk. Few treatments are available to prevent CKD in type 2 diabetes. Objective: To test whether supplementation with vitamin D3 or omega-3 fatty acids prevents development or progression of CKD in type 2 diabetes. Design, Setting, and Participants: Randomized clinical trial with a 2 × 2 factorial design conducted among 1312 adults with type 2 diabetes recruited between November 2011 and March 2014 from all 50 US states as an ancillary study to the Vitamin D and Omega-3 Trial (VITAL), coordinated by a single center in Massachusetts. Follow-up was completed in December 2017. Interventions: Participants were randomized to receive vitamin D3 (2000 IU/d) and omega-3 fatty acids (eicosapentaenoic acid and docosahexaenoic acid; 1 g/d) (n = 370), vitamin D3 and placebo (n = 333), placebo and omega-3 fatty acids (n = 289), or 2 placebos (n = 320) for 5 years. Main Outcomes and Measures: The primary outcome was change in glomerular filtration rate estimated from serum creatinine and cystatin C (eGFR) from baseline to year 5. Results: Among 1312 participants randomized (mean age, 67.6 years; 46% women; 31% of racial or ethnic minority), 934 (71%) completed the study. Baseline mean eGFR was 85.8 (SD, 22.1) mL/min/1.73 m2. Mean change in eGFR from baseline to year 5 was -12.3 (95% CI, -13.4 to -11.2) mL/min/1.73 m2 with vitamin D3 vs -13.1 (95% CI, -14.2 to -11.9) mL/min/1.73 m2 with placebo (difference, 0.9 [95% CI, -0.7 to 2.5] mL/min/1.73 m2). Mean change in eGFR was -12.2 (95% CI, -13.3 to -11.1) mL/min/1.73 m2 with omega-3 fatty acids vs -13.1 (95% CI, -14.2 to -12.0) mL/min/1.73 m2 with placebo (difference, 0.9 [95% CI, -0.7 to 2.6] mL/min/1.73 m2). There was no significant interaction between the 2 interventions. Kidney stones occurred among 58 participants (n = 32 receiving vitamin D3 and n = 26 receiving placebo) and gastrointestinal bleeding among 45 (n = 28 receiving omega-3 fatty acids and n = 17 receiving placebo). Conclusions and Relevance: Among adults with type 2 diabetes, supplementation with vitamin D3 or omega-3 fatty acids, compared with placebo, resulted in no significant difference in change in eGFR at 5 years. The findings do not support the use of vitamin D or omega-3 fatty acid supplementation for preserving kidney function in patients with type 2 diabetes. Trial Registration: ClinicalTrials.gov Identifier: NCT01684722.

Vitamin D and omega-3 trial to prevent and treat diabetic kidney disease: Rationale, design, and baseline characteristics.

Diabetic kidney disease (DKD), defined as reduced glomerular filtration rate (GFR), elevated urine albumin excretion, or both that is clinically attributable to diabetes, is a common and morbid diabetes complication. Animal-experimental data, observational human studies, and short-term clinical trials suggest that vitamin D and omega-3 fatty acid supplements may be safe and inexpensive interventions to reduce the incidence and progression of DKD. The Vitamin D and Omega-3 Trial to Prevent and Treat DKD (VITAL-DKD) was designed as an ancillary study to the VITAL trial of 25,871 US adults. In a 2 × 2 factorial design, VITAL participants were randomly assigned to vitamin D3 (cholecalciferol, 2000 IU daily) or placebo and to marine omega-3 fatty acids (eicospentaenoic acid and docosahexaenoic acid, 1 g/d) or placebo. VITAL-DKD enrolled a subset of 1326 VITAL participants with type 2 diabetes at baseline to test the effects of vitamin D and omega-3 fatty acids on changes in estimated GFR and urine albumin excretion. Over five years of follow-up, VITAL-DKD collected blood and urine samples to quantify changes in estimated GFR (the primary study outcome) and urine albumin excretion. At baseline, mean age of VITAL-DKD participants was 67.6 years, 46% were women, 30% were of racial or ethnic minority, and the prevalence of DKD (estimated GFR <60 mL/min/1.73m2 or urine albumin-creatinine ratio ≥ 30 mg/g) was 17%. In this type 2 diabetes population, VITAL-DKD will test the hypotheses that vitamin D and omega-3 fatty acids help prevent the development and progression of DKD.

Effect of Coenzyme Q10 on Biomarkers of Oxidative Stress and Cardiac Function in Hemodialysis Patients: The CoQ10 Biomarker Trial.

BACKGROUND: Oxidative stress is highly prevalent in patients with end-stage renal disease and is linked to excess cardiovascular risk. Identifying therapies that reduce oxidative stress has the potential to improve cardiovascular outcomes in patients undergoing maintenance dialysis. STUDY DESIGN: Placebo-controlled, 3-arm, double-blind, randomized, clinical trial. SETTING & PARTICIPANTS: 65 patients undergoing thrice-weekly maintenance hemodialysis. INTERVENTION: Patients were randomly assigned in a 1:1:1 ratio to receive once-daily coenzyme Q10 (CoQ10; 600 or 1,200mg) or matching placebo for 4 months. OUTCOMES: The primary outcome was plasma oxidative stress, defined as plasma concentration of F2-isoprotanes. Secondary outcomes included levels of plasma isofurans, levels of cardiac biomarkers, predialysis blood pressure, and safety/tolerability. MEASUREMENTS: F2-isoprostanes and isofurans were measured as plasma markers of oxidative stress, and N-terminal pro-brain natriuretic peptide and troponin T were measured as cardiac biomarkers at baseline and 1, 2, and 4 months. RESULTS: Of 80 randomly assigned patients, 15 were excluded due to not completing at least 1 postbaseline study visit and 65 were included in the primary intention-to-treat analysis. No treatment-related major adverse events occurred. Daily treatment with 1,200mg, but not 600mg, of CoQ10 significantly reduced plasma F2-isoprostanes concentrations at 4 months compared to placebo (adjusted mean changes of -10.7 [95% CI, -7.1 to -14.3] pg/mL [P<0.001] and -8.3 [95% CI, -5.5 to -11.0] pg/mL [P=0.1], respectively). There were no significant effects of CoQ10 treatment on levels of plasma isofurans, cardiac biomarkers, or predialysis blood pressures. LIMITATIONS: Study not powered to detect small treatment effects; difference in baseline characteristics among randomized groups. CONCLUSIONS: In patients undergoing maintenance hemodialysis, daily supplementation with 1,200mg of CoQ10 is safe and results in a reduction in plasma concentrations of F2-isoprostanes, a marker of oxidative stress. Future studies are needed to determine whether CoQ10 supplementation improves clinical outcomes for patients undergoing maintenance hemodialysis.

A pilot randomized crossover trial assessing the safety and short-term effects of pomegranate supplementation in hemodialysis patients.

OBJECTIVE: Oxidative stress and systemic inflammation are highly prevalent in patients undergoing maintenance hemodialysis (MHD) and are linked to excess cardiovascular risk. This study examined whether short-term supplementation with pomegranate juice and extract is safe and well tolerated by MHD patients. The secondary aim was to assess the effect of pomegranate supplementation on oxidative stress, systemic inflammation, monocyte function, and blood pressure. DESIGN: Prospective, randomized, crossover, pilot clinical trial (NCT01562340). SETTING: The study was conducted from March to October 2012 in outpatient dialysis facilities in the Seattle metropolitan area. SUBJECTS: Twenty-four patients undergoing MHD (men, 64%; mean age, 61 ± 14 years) were randomly assigned to receive pomegranate juice or extract during a 4-week intervention period. After a washout period, all patients received the alternative treatment during a second 4-week intervention period. INTERVENTION: Patients assigned to receive pomegranate juice received 100 mL of juice before each dialysis session. Patients assigned to receive pomegranate extract were given 1,050 mg of extract daily. MAIN OUTCOME MEASURES: The main outcome measures were safety and tolerability of pomegranate juice and extract. Additional secondary outcomes assessed included serum lipids, laboratory biomarkers of inflammation (C-reactive protein and interleukin 6) and oxidative stress (plasma F2 isoprostanes and isofurans), monocyte cytokine production, and predialysis blood pressure. RESULTS: Both pomegranate juice and extract were safe and well tolerated by study participants. Over the study period, neither treatment had a significant effect on lipid profiles, plasma C-reactive protein, interleukin 6, F2-isoprostane or isofuran concentrations, predialysis systolic or diastolic blood pressure nor changed the levels of monocyte cytokine production. CONCLUSIONS: Both pomegranate juice and extract are safe and well tolerated by patients undergoing MHD but do not influence markers of inflammation or oxidative stress nor affect predialysis blood pressure.

A phase II randomized placebo-controlled trial of omega-3 fatty acids for the treatment of acute lung injury.

OBJECTIVES: Administration of eicosapentaenoic acid and docosahexanoic acid, omega-3 fatty acids in fish oil, has been associated with improved patient outcomes in acute lung injury when studied in a commercial enteral formula. However, fish oil has not been tested independently in acute lung injury. We therefore sought to determine whether enteral fish oil alone would reduce pulmonary and systemic inflammation in patients with acute lung injury. DESIGN: Phase II randomized controlled trial. SETTING: Five North American medical centers. PATIENTS: Mechanically ventilated patients with acute lung injury ≥18 yrs of age. INTERVENTIONS: Subjects were randomized to receive enteral fish oil (9.75 g eicosapentaenoic acid and 6.75 g docosahexanoic acid daily) or saline placebo for up to 14 days. MEASUREMENTS AND MAIN RESULTS: Bronchoalveolar lavage fluid and blood were collected at baseline (day 0), day 4 ± 1, and day 8 ± 1. The primary end point was bronchoalveolar lavage fluid interleukin-8 levels. Forty-one participants received fish oil and 49 received placebo. Enteral fish oil administration was associated with increased serum eicosapentaenoic acid concentration (p < .0001). However, there was no significant difference in the change in bronchoalveolar lavage fluid interleukin-8 from baseline to day 4 (p = .37) or day 8 (p = .55) between treatment arms. There were no appreciable improvements in other bronchoalveolar lavage fluid or plasma biomarkers in the fish oil group compared with the control group. Similarly, organ failure score, ventilator-free days, intensive care unit-free days, and 60-day mortality did not differ between the groups. CONCLUSIONS: Fish oil did not reduce biomarkers of pulmonary or systemic inflammation in patients with acute lung injury, and the results do not support the conduct of a larger clinical trial in this population with this agent. This experimental approach is feasible for proof-of-concept studies evaluating new treatments for acute lung injury.

Duffy antigen facilitates movement of chemokine across the endothelium in vitro and promotes neutrophil transmigration in vitro and in vivo.

The Duffy Ag expressed on RBCs, capillaries, and postcapillary venular endothelial cells binds selective CXC and CC chemokines with high affinity. Cells transfected with the Duffy Ag internalize but do not degrade chemokine ligand. It has been proposed that Duffy Ag transports chemokines across the endothelium. We hypothesized that Duffy Ag participates in the movement of chemokines across the endothelium and, by doing so, modifies neutrophil transmigration. We found that the Duffy Ag transfected into human endothelial cells facilitates movement of the radiolabeled CXC chemokine, growth related oncogene-alpha/CXC chemokine ligand 1 (GRO-alpha/CXCL1), across an endothelial monolayer. In addition, neutrophil migration toward GRO-alpha/CXCL1 and IL-8 (IL-8/CXCL8) was enhanced across an endothelial monolayer expressing the Duffy Ag. Furthermore, GRO-alpha/CXCL1 stimulation of endothelial cells expressing the Duffy Ag did not affect gene expression by oligonucleotide microarray analysis. These in vitro observations are supported by the finding that IL-8/CXCL8-driven neutrophil recruitment into the lungs was markedly attenuated in transgenic mice lacking the Duffy Ag. We conclude that Duffy Ag has a role in enhancing leukocyte recruitment to sites of inflammation by facilitating movement of chemokines across the endothelium.

Randomized, prospective trial of antioxidant supplementation in critically ill surgical patients.

OBJECTIVE: To determine the effectiveness of early, routine antioxidant supplementation using alpha-tocopherol and ascorbic acid in reducing the rate of pulmonary morbidity and organ dysfunction in critically ill surgical patients. SUMMARY BACKGROUND DATA: Oxidative stress has been associated with the development of the acute respiratory distress syndrome (ARDS) and organ failure through direct tissue injury and activation of genes integral to the inflammatory response. In addition, depletion of endogenous antioxidants has been associated with an increased risk of nosocomial infections. The authors postulated that antioxidant supplementation in critically ill surgical patients may reduce the incidence of ARDS, pneumonia, and organ dysfunction. METHODS: This randomized, prospective study was conducted to compare outcomes in patients receiving antioxidant supplementation (alpha-tocopherol and ascorbate) versus those receiving standard care. The primary endpoint for analysis was pulmonary morbidity (a composite measure of ARDS and nosocomial pneumonia). Secondary endpoints included the development of multiple organ failure, duration of mechanical ventilation, length of ICU stay, and mortality. RESULTS: Five hundred ninety-five patients were enrolled and analyzed, 91% of whom were victims of trauma. The relative risk of pulmonary morbidity was 0.81 (95% confidence interval 0.60-1.1) in patients receiving antioxidant supplementation. Multiple organ failure was significantly less likely to occur in patients receiving antioxidants than in patients receiving standard care, with a relative risk of 0.43 (95% confidence interval 0.19-0.96). Patients randomized to antioxidant supplementation also had a shorter duration of mechanical ventilation and length of ICU stay. CONCLUSIONS: The early administration of antioxidant supplementation using alpha-tocopherol and ascorbic acid reduces the incidence of organ failure and shortens ICU length of stay in this cohort of critically ill surgical patients.