(KIWI) Speeding up a Slow Protein for Muscle Mass With Hay Kiwifruit

The specific hypothesis is that the consumption of 2 Hayward green kiwifruit (containing actinidin protease) prior to 100g of ground beef will increase the rate of protein digestion from the beef in the elderly, leading to an increased uptake of the essential amino acids. Furthermore, this increased essential amino acid availability will produce a greater postprandial net anabolic protein response, as well as increased fractional synthetic rates of muscle proteins.

Study Overview

• Status: Completed
• Conditions: Protein; Metabolism
• Intervention / Treatment: Dietary supplement: Green Hayward Kiwifruit first, then Gold Kiwifruit; Dietary supplement: Gold Kiwifruit First, then Green Hayward Kiwifruit

Detailed Description

The specific hypothesis is that the consumption of 2 Hayward green kiwifruit (containing actinidin protease) prior to 100g of ground beef will increase the rate of protein digestion from the beef in the elderly, leading to an increased uptake of the essential amino acids. Furthermore, this increased essential amino acid availability will produce a greater postprandial net anabolic protein response, as well as increased fractional synthetic rates of muscle proteins.

To test this hypothesis, the investigators will use a double-blinded crossover design involving two intervention arms; in both arms 100g of ground beef (cooked weight) will be consumed following either 2 Hayward green kiwifruit (containing actinidin protease) or 2 Hort16A Gold kiwifruit (devoid of actinidin protease) by elderly subjects.

• Study Type: Interventional
• Enrollment (Actual): 13
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Arkansas
    • Little Rock, Arkansas, United States, 72205
      • UAMS Center on Aging

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 60 years to 85 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• men and women ages 60-85 inclusive.

Exclusion Criteria:

• Inability to chew meats or difficulty swallowing solid foods
• History of diabetes
• History of malignancy in the 6 months prior to enrolment
• History of gastrointestinal reduction or bypass surgery (Lapband, etc)
• History of a chronic inflammatory condition or disease (Lupus, HIV'AIDS, etc)
• History of chronic kidney disease or currently requiring dialysis.
• Allergy to beef or kiwifruit
• Subjects who do not or will not eat animal proteins
• Subjects who cannot refrain from consuming protein or amino acid supplements during their participation in this study
• Subjects who report regular resistance exercise (more than once per week)
• Hemoglobin less than 9.5mg/dL at the screening visit
• Platelets less than <150,000 at the screening visit
• Subjects who are not willing or able to suspend aspirin for several days prior to their muscle biopsies.
• Subjects who have been prescribed a blood-thinning medication (Coumadin, lovenox, heparin, Plavix, etc).
• Concomitant use of corticosteroids (ingestion, injection or transdermal)
• Any other disease or condition that would place the subject at increased risk of harm if they were to participate, at the discretion of the study physician

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Other
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Quadruple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Placebo Comparator: Gold Kiwifruit First, then Green Hayward Kiwifruit; Subjects first ate 2 gold kiwifruit with midday meal for 2 weeks before crossing over to the green Hayward kiwifruit intervention	Dietary supplement: Green Hayward Kiwifruit first, then Gold Kiwifruit; Subjects ate 2 peeled green kiwifruit with their midday meal for 2 weeks prior to testing.; Dietary supplement: Gold Kiwifruit First, then Green Hayward Kiwifruit; Subjects ate 2 peeled gold kiwifruit with their midday meal for 2 weeks prior to testing.
Active Comparator: Green Hayward Kiwifruit first, then Gold Kiwifruit; Subjects first ate 2 green Hayward kiwifruit with midday meal for 2 weeks before crossing over to the gold kiwifruit intervention	Dietary supplement: Green Hayward Kiwifruit first, then Gold Kiwifruit; Subjects ate 2 peeled green kiwifruit with their midday meal for 2 weeks prior to testing.; Dietary supplement: Gold Kiwifruit First, then Green Hayward Kiwifruit; Subjects ate 2 peeled gold kiwifruit with their midday meal for 2 weeks prior to testing.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Whole Body Net Balance Measured by Gas Chromatography-Mass Spectrometry (GC-MS)	Blood samples were analyzed to quantify the appearance of the stable isotopes: 2H2-tyrosine, 2H4-tyrosine, and 2H5-phenylalanine in tracer to tracee ratio or mole percent excess. Changes in these markers over time enable the calculation of whole body protein metabolism. Calculations are done as follows: Total plasma rate of appearance = infusion rate/enrichment Fractional rate of appearance of tyrosine from phenylalanine= 2H4-tyrosine/2H5-phenylalanine Phenylalanine hydroxylation = fractional rate of appearance of tyrosine from phenylalanine x rate of appearance of tyrosine Protein Synthesis = [(rate of appearance of phenylalanine -Phe hydroxylation) x 25] Protein Breakdown = [(rate of appearance of phenylalanine - phenylalanine infusion rate) x 25 - phenylalanine intake] Net Balance = Protein Synthesis - Protein Breakdown	300 minutes

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Skeletal Muscle Protein Metabolism Measured by Gas Chromatography-Mass Spectrometry (GC-MS)	Muscle samples were analyzed to quantify the appearance of the stable isotope 2H5-phenylalanine in trace to tracee ratio or mole percent excess. The change in 2H5-phenylalanine in subsequent muscle biopsy allow for the calculation of muscle protein synthesis. The calculation is done as follows: [(2H5-phenylalanine enrichment in second biopsy - 2H5-phenylalanine enrichment in second biopsy)/ (2H5-phenylalanine plasma enrichment × time)] × 60 × 100.	9.5 hours

Collaborators and Investigators

• Sponsor: University of Arkansas
• Investigators: Principal Investigator: Arny A Ferrando, Ph.D., UAMS professor

Publications and helpful links

General Publications

• Park S, Church DD, Starck C, Schutzler SE, Azhar G, Kim IY, Ferrando AA, Moughan PJ, Wolfe RR. The impact of Hayward green kiwifruit on dietary protein digestion and protein metabolism. Eur J Nutr. 2021 Mar;60(2):1141-1148. doi: 10.1007/s00394-020-02363-5. Epub 2020 Sep 24. Erratum In: Eur J Nutr. 2020 Dec 11;:

Study record dates

Study Major Dates

• Study Start (Actual): July 1, 2018
• Primary Completion (Actual): November 20, 2018
• Study Completion (Actual): November 20, 2018

Study Registration Dates

• First Submitted: April 15, 2020
• First Submitted That Met QC Criteria: April 17, 2020
• First Posted (Actual): April 22, 2020

Study Record Updates

• Last Update Posted (Actual): November 4, 2021
• Last Update Submitted That Met QC Criteria: October 7, 2021
• Last Verified: October 1, 2021

More Information

Terms related to this study

• Other Study ID Numbers: 206814

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: No

Drug and device information, study documents

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