Postprandial Amino Acid Response After Protein Consumption (PAR)

The Acute Postprandial Response of Blood Amino Acids in Older Adults After Consumption of Dairy Protein, Plant Protein and Their Blend

Increasing muscle protein synthesis via protein-based nutrition, with or without exercise, maintains a strong, healthy muscle mass, which in turn leads to improved health, independence and functionality in older adults. There is increased interest in plant-based proteins, but these have in general a lower anabolic effect than animal proteins. Various strategies have been suggested to augment the anabolic properties of plant proteins, including using plant-animal protein blends. However, only little is known yet about the anabolic properties of such an approach. As the peripheral metabolic availability of proteins is an important aspect that has to be taken into account when screening the anabolic properties of protein sources/blends, it is the aim of this study to investigate the postprandial AA response of milk protein, micellar casein, pea protein, and a milk protein-pea protein blend in healthy older adults.

Study Overview

• Status: Not yet recruiting
• Conditions: Sarcopenia
• Intervention / Treatment: Dietary supplement: milk protein; Dietary supplement: micellar casein; Dietary supplement: pea protein; Dietary supplement: milk/pea protein blend

Detailed Description

Objective:

The primary objective is to quantify the postprandial area under the curve (iAUC), the maximal level (Cmax) and the time profile (Tmax) of blood amino acids after ingestion of milk protein, micellar casein, pea protein, and a milk protein-pea protein blend in healthy older adults.

Secondary objectives are to quantify the postprandial insulin response, and to quantify the potential muscular response, using an in vitro muscle cell assay, of postprandial blood derived from healthy older adults after ingestion of milk protein, micellar casein, pea protein, and a milk protein-pea protein blend.

Study design: The study is designed as a randomized, single-blinded within-subject (cross-over) trial in which a group of 12 subjects receive 4 different protein drinks.

Study population: Healthy older adults (60-80 years) Intervention (if applicable): Four different protein drinks will be investigated: milk protein, micellar casein, pea protein, and a milk protein/ pea protein blend. All drinks will contain a 20 gram protein load. All protein supplements will be mixed with 250 mL water and contain some additional non-caloric flavorings.

Main study parameters/endpoints: Postprandial blood amino acid response, up to 5 hours after consumption of a protein drink measured (incremental area under curve, Cmax and Tmax).

• Study Type: Interventional
• Enrollment (Anticipated): 12
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Netherlands
  • Gelderland
    • Wageningen, Gelderland, Netherlands, 6703 HA
      • Division of Human Nutrition, Wageningen University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 60 years to 80 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Age ≥60 and ≤80
• BMI ≥20 and ≤32 kg/m2
• Non-smoking
• Healthy as assessed by a lifestyle and health questionnaire ("Verklaring leefgewoonten en gezondheid") and according to the judgment of the study physician.
• Regular and normal Dutch eating habits as assessed by a lifestyle and health questionnaire (3 main meals per day)
• Veins suitable for cannulation (blood sampling)
• Voluntary participation
• Having given written informed consent
• Willing to comply with study procedures
• Accept use of all encoded data, including publication, and the confidential use and storage of all data for 15 years.
• Accept disclosure of the financial benefit of participation in the study to the authorities concerned

Exclusion Criteria:

• Participation in any clinical trial including blood sampling and/or administration of substances up to 30 days before day 1 of this study
• Having a history of medical or surgical events that may significantly affect the study outcome, including: Inflammatory bowel disease, hepatitis, pancreatitis, ulcers, gastrointestinal or rectal bleeding; major gastrointestinal tract surgery such as gastrectomy, gastroenterostomy, or bowel resection; known or suspected gastrointestinal disorders, colon or GI tract cancer
• Use of the following medication: glucose lowering drugs, insulin; medication that may impact gastric emptying (e.g. gastric acid inhibitors or laxatives)
• Diagnosed with diabetes, being treated for high blood glucose or increased fasting blood glucose (> 7 mmol/l in finger prick blood) as assessed during screening visit
• For men: Hb <8,5 mmol/l as assessed during screening visit; for women: Hb <7,5 mmol/l
• Use of protein supplements
• Mental status that is incompatible with the proper conduct of the study
• A self-reported reported food allergy or sensitivity to dairy or plant ingredients
• Alcohol consumption for men > 28 units/week and >4/day; for women: >21 units/week and >3/day
• Reported unexpected weight loss or weight gain of > 3 kg in the month prior to pre-study screening, or intention to lose weight during the study period
• Reported slimming or medically prescribed diet
• Recent blood donation (<1 month prior to Day 01 of the study)
• Not willing to give up blood donation during the study
• Not having a general practitioner
• Not willing to accept information-transfer concerning participation in the study, or information regarding his or her health, like laboratory results and eventual adverse events to and from his general practitioner

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Double

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: milk protein; milk protein supplement	Dietary supplement: milk protein; milk protein supplement
Experimental: micellar casein; casein supplement	Dietary supplement: micellar casein; micellar casein supplement
Experimental: pea protein; pea protein supplement	Dietary supplement: pea protein; pea protein supplement
Experimental: milk/pea protein; a blend of milk and pea protein	Dietary supplement: milk/pea protein blend; milk/pea protein supplement

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
plasma AA	postprandial plasma AA response	5 hours

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Insulin	postprandial insulin response	3 hours

Collaborators and Investigators

• Sponsor: Wageningen University
• Collaborators: NIZO Food Research; Ingredia S.A.

Study record dates

Study Major Dates

• Study Start (Anticipated): November 1, 2021
• Primary Completion (Anticipated): December 31, 2021
• Study Completion (Anticipated): July 1, 2022

Study Registration Dates

• First Submitted: June 11, 2021
• First Submitted That Met QC Criteria: June 11, 2021
• First Posted (Actual): June 23, 2021

Study Record Updates

• Last Update Posted (Actual): June 29, 2021
• Last Update Submitted That Met QC Criteria: June 23, 2021
• Last Verified: June 1, 2021

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Nervous System Diseases; Neurologic Manifestations; Neuromuscular Manifestations; Pathological Conditions, Anatomical; Muscular Atrophy; Atrophy; Sarcopenia; Molecular Mechanisms of Pharmacological Action; Chelating Agents; Sequestering Agents; Caseins
• Other Study ID Numbers: NL78067.028.21

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No