Development of a Metabolic Assessment Tool for Chronic Kidney Disease
Condition: Immunoglobulin A Nephropathy; Healthy Subjects
MeSH terms: Kidney Diseases; Renal Insufficiency, Chronic; Glomerulonephritis, IGA
Study type: Interventional

Summary: 
      The purpose of this study is to examine the variation between individuals in blood lipid
      metabolites, and the changes in these metabolites in response to omega-3 fatty acids in
      patients with immunoglobulin A nephropathy (IgAN) and in healthy subjects. The hypothesis is
      that measuring variation among individuals and changes in response to omega-3 fatty acids
      comprehensively by using metabolomics will help to identify those individuals who are
      responders and those who are non-responders to omega-3 fatty acids as an anti-inflammatory
      intervention.
    

Detailed description: 
      It is unclear how metabolomic profiles of individuals change in response to short-term
      intervention with omega-3 fatty acids. It is necessary to establish the means and standard
      deviations in the levels of omega-3 fatty acids and their related metabolites in healthy
      subjects and in different disease states in order to better understand the mechanisms related
      to lipid metabolism of metabolic diseases that are modified by omega-3 fatty acids.
      Specifically, the project will examine the metabolomic profiles of healthy controls and
      patients with immunoglobulin A nephropathy (IgAN) before and after an omega-3 fatty acid
      intervention. The IgAN patient samples were obtained from collaborators from a previously
      completed project. The healthy subjects were tested in a small pilot trial conducted at UC
      Davis as described below.

        -  Twelve healthy volunteers willing and able to take 6 g of fish oil for 6 weeks were
           recruited from the general UC Davis population including students, faculty, and staff.
           The volunteers were recruited by personal communication at seminars and other
           school-related activities as well as flyers posted on campus.

        -  The volunteers were contacted and scheduled for a screening and consent visit. Subjects
           who met all eligibility criteria and signed a consent form were then scheduled for a
           baseline blood draw and to collect a first morning urine sample. A research team member
           contacted each subject the day before their first scheduled study date to confirm and
           remind the subject about fasting, about collecting the first morning urine void, and the
           time and location of the study.

        -  On each study visit, the participants came to the Ragle Human Nutrition Center (1283
           Academic Surge) between 7 and 9 am after an overnight fast, at which point they were
           weighed (clothed but with no shoes) on a digital scale and their height was measured. A
           registered phlebotomist drew 20 mL of blood by venipuncture for their baseline blood
           draw. Subjects also brought in their first morning urine sample at this time. Subjects
           were then given their fish oil capsules that were separated in a Ziploc bag for each
           week of the intervention. Subjects took the fish oil capsules at home at their own
           discretion but study personnel suggested they take the capsules after their last meal of
           the day and before bed each evening. Study personnel contacted subjects throughout the
           course of the study by phone and/or e-mail to make sure that there were no adverse
           effects from the fish oil and to ensure compliance. Subjects were instructed to record
           their diets through 24-hour dietary recalls before the baseline blood draw, and at 3
           additional time points throughout the study.

        -  Immediately after blood collection, the researchers separated the red blood cells and
           peripheral blood mononuclear cells (PBMC) from the plasma, aliquoted the samples, and
           then stored them in a -70°C freezer for future analysis.
    

Intervention name(s): Fish Oil
Intervention type(s): Dietary Supplement
Intervention description(s): Ocean Nutrition Fish Oil Capsules containing 1.9 g eicosapentaenoic acid (EPA) and 1.5 g docosahexaenoic acid (DHA)
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Basic Science
Keywords: Fish oil; Omega-3 fatty acids