Monocyte function in healthy middle-aged people receiving fermented milk containing Lactobacillus casei.
BACKGROUND
Lactic acid bacteria have been suggested as a dietary strategy to enhance immune system activity.


OBJECTIVE
The aim of the current work was to test the effects of a Lactobacillus casei fermented milk consumption on monocyte activity of middle-aged volunteers.


METHODS
Forty-five healthy volunteers, 24 women and 21 men (aged: 51 - 58 years), were randomized in two groups to receive three cups per day of a fermented milk containing L. casei DN114001 (108 - 1010/g) (n = 23), or placebo (n = 22), during 8 weeks. White blood cell count and the oxidative burst capacity of monocytes and granulocytes were examined with a FACScalibur. Measurements were performed at baseline and after the nutritional intervention, at day fifty-six.


RESULTS
After the trial, no changes in immune cell proportions were detected in both groups, as well as in monocyte activity after the placebo consumption (p = 0.625). However, volunteers included in the probiotic-treated group increased (p = 0.029) their oxidative burst capacity of monocytes, and this increment inversely and significantly correlated with the intensity registered at baseline (r = -0.653, p = 0.004).


CONCLUSIONS
Results showed that daily intake of fermented milk containing Lactobacillus casei was able to module the oxidative burst capacity of monocyte subset in healthy middle-aged people, particularly in subjects with lower initial levels. Thus, this nutritional strategy could be considered to maintain immune competence in ageing.
Department of Physiology and Nutrition, University of Navarra (Edif. Investigación), C/ Irunlarrea, s/n, 31008 Pamplona, Spain.
D
D
Parra
B Martinez
BM
De Morentin
J M
JM
Cobo
A
A
Mateos
J A
JA
Martinez
D000375:Aging / Q000276:immunology*; D043302:Cultured Milk Products / Q000276:immunology*; D004311:Double-Blind Method; D005260:Female; D005285:Fermentation; D005434:Flow Cytometry; D006801:Humans; D007780:Lacticaseibacillus casei; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000502:physiology*; D010919:Placebos; D019936:Probiotics; D016897:Respiratory Burst / Q000187:drug effects*
D010919:Placebos