Chronic Kidney Failure
Conditions
Keywords
CKD, Hemodialysis, Protein Digestion, Fat Digestion, Gut Function, Glucose Absorption, Muscle Function
Brief summary
Weight loss commonly occurs in patients with chronic kidney disease (CKD), negatively influencing their quality of life, treatment response and survival. Loss of muscle protein is generally a central component of weight loss in CKD patients but patients also have reductions in fat mass and bone density, independent of the severity of the disease state. Attempts to reverse weight and muscle loss in CKD and improve nutritional status by nutritional supplementation have been unsuccessful and there are currently no approved therapies. Purpose of this study is to provide detailed insight in disease related gut function by obtaining information on gut permeability, digestion and absorption of glucose, fat and protein in CKD patients compared to matched healthy controls. Additionally, to examine whether protein and amino acid metabolism is disturbed in CKD patients compared to healthy controls. This will provide required information that will lead to implement new strategies to develop optimal nutritional regimen in order to enhance nutritional status, quality of life and survival in relation to kidney disease.
Detailed description
This study involves one test day of approximately 7-8 hours. On this test day subjects will ingest a sugar drink to assess gut permeability and gut function, and a protein meal to measure digestion/absorption and the anabolic response to food intake. Subjects will also receive a mixture of amino acids that are made a little heavier than normal, called stable isotopes. This stable isotopes is used to investigate protein behavior in the body (protein kinetics). Blood (100-120 ml in total) and urine samples will be collected over 7.5 hours.
Interventions
DIETARY_SUPPLEMENTBoost High Protein
Subjects will receive stable amino acid isotopes IV and will receive Boost High Protein with added isotopes to measure anabolic response to a meal.
Sponsors
Texas A&M University
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
SUPPORTIVE_CARE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
55 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
CKD subjects * Ability to walk, sit down and stand up independently * Age 55 years or older * Ability to lie in supine or elevated position for 7 hours * Diagnosis of kidney disease; undergoing hemodialysis * Clinically stable condition; no hospitalization 4 weeks preceding first study day * Willingness and ability to comply with the protocol Inclusion criteria healthy subjects: * Healthy male or female according to the investigator's or appointed staff's judgment * Ability to walk, sit down and stand up independently * Age 55 years or older (older control group) * Ability to lay in supine or elevated position for 7 hours * No diagnosis of CKD * Willingness and ability to comply with the protocol
Exclusion criteria
all subjects: * Any condition that may interfere with the definition 'healthy subject' according to the investigator's judgment (healthy subjects only) * Established diagnosis of malignancy * Established diagnosis of Insulin Dependent Diabetes Mellitus * History of untreated metabolic diseases including hepatic disorder * Presence of acute illness or metabolically unstable chronic illness * Presence of fever within the last 3 days * Body mass index \>40 kg/m2 (healthy subjects only) * Any other condition that would interfere with the study or safety of the patient (according to the PI or nurse) * Use of protein or amino acid containing nutritional supplements within 5 days of first study day * Use of long-term oral corticosteroids or short course of oral corticosteroids within 4 weeks preceding first study day * Failure to give informed consent or Investigator's uncertainty about the willingness or ability of the subject to comply with the protocol requirements * (Possible) pregnancy
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Net whole-body protein synthesis | 0, 15, 30, 45, 60, 75, 90, 105, 120, 150, 180, 210 min post-meal | Change in whole-body protein synthesis rate after intake of meal |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Glucose absorption | 7 hours | Recovery of 3-O-Methyl-D-glucose in the urine. |
| Gut permeability | 7 hours | Recovery of rhamnose/lactulose in urine |
| Skeletal and respiratory muscle strength | 1 day | Difference in leg strength and fatigue, handgrip strength and fatigue, and inspiratory and expiratory pressure between heart failure patients and healthy controls. |
| Cognitive function | 1 day | Outcome of neuro-psychological tests in heart failure patients and healthy controls in relation to the tryptophan metabolism |
| Fatty acid digestion after feeding | 0,15,30,45,60,75,90,105,120,150,180,210 min post-meal | Enrichment in palmitic acid and tripalmitin fatty acids in plasma |
| Protein digestion after feeding | 0,15,30,45,60,75,90,105,120,150,180,210, min post-meal | Ratio enrichment free phenylalanine vs phenylalanine from protein spirulina |
| Arginine turnover rate | Postabsorptive state during 3 hours | Arginine enrichment in plasma |
| Citrulline Rate of appearance | Postabsorptive state during 3 hours | Plasma enrichment of citrulline |
| Tryptophan turnover rate | Postabsorptive state during 3 hours | Tryptophan enrichment in plasma |
| Insulin response to feeding | During 3 hours after feeding | Acute change from postabsorptive state after intake of meal |
| Fat-free mass | Postabsorptive state during 15 min | Characteristics of study subjects |
| Myofibrillar protein breakdown rate | 0,15,30,45,60,75,90,105,120,150,180,210 min post-meal | 3-Methylhistidine enrichment in plasma |
| Glycine rate of appearance | Postabsorptive state during 3 hours | Glycine enrichment in plasma |
| Taurine turnover rate | Postabsorptive state during 3 hours | Enrichment of taurine in plasma |
| Whole body collagen breakdown rate | Postabsorptive state during 3 hours | Hydroxyproline enrichment in plasma |
Countries
United States
Outcome results
None listed