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Probiotic Studies in Neonatal Mice Using Gavage
Published on: January 27, 2019
Effect of hydrolyzed milk proteins and postbiotic Lacticaseibacillus rhamnosus GG on inflammatory responses in
Selenius Otto1, Hieta Janina2, Aittoniemi Janne3
1Nutrition and Food Research Center, Faculty of Medicine, University of Turku, Turku, Finland.
Background:
Low-grade inflammation (LGI) and increased infection susceptibility are common under sustained stress. We investigated whether daily consumption of hydrolyzed milk protein (HMP), alone or combined with heat-killed Lacticaseibacillus rhamnosus GG (HK-LGG), reduces LGI in healthy young Finnish conscripts, with serum high-sensitivity C-reactive protein (hs-CRP) as the primary outcome. Secondary outcomes included additional inflammatory biomarkers (calprotectin, haptoglobin, suPAR), sick days, stress, fitness, and recovery metrics.
Methods:
In this eight-week randomized, double-blinded, placebo-controlled pilot trial, 160 conscripts (157 male) received milk beverages containing either maltodextrin (Control; 9.5g protein; n=53), HMP (19.5g protein; n=53), or HMP (19.3g protein; n=54) with HK-LGG (2×109 cells) daily, administered in two 250ml portions. We assessed the following factors: fasting serum markers of LGI, anthropometrics, smartwatch-based activity, recovery, fitness test metrics, self-reported sick days, and stress and fatigue questionnaire scores.
Results:
Between-group differences in changes over the intervention period were observed for hs-CRP (p=0.02) and calprotectin (p=0.04). Over time the increase in hs-CRP from baseline was lower in the HMP vs HMP+HK-LGG group (ratio of geometric means 0.45; 95% CI 0.21-0.95; p= 0.03), whereas post hoc comparisons for calprotectin showed no between-group differences. No differences were observed between the treatment groups in haptoglobin (p = 0.53) or suPAR (p = 0.14). Infection prevalence was highest in the HMP+HK-LGG group (60.5%) compared with the HMP group (34.1%; p = 0.045), whereas the Control group (45.2%) did not differ from either group. The interventions did not impact body weight, activity, recovery, or fitness test outcomes.
Conclusion:
HMP may help stabilize immune responses during physical and infectious stress in conscripts, although these effects did not extend to fitness or recovery outcomes. The potential postbiotic HK-LGG showed no additional benefit when combined with HMP, calling for further evaluation of its efficacy in high stress and infection risk populations.
Registration Number Of Clinical Trial:
NCT06355089 (https://www.
Clinicaltrials:
gov/study/NCT06355089; registered on March 21, 2024).