Efficacy of heat-killed Lactococcus lactis JCM 5805 on immunity and fatigue during consecutive high intensity exercise in male athletes: a randomized, placebo-controlled, double-blinded trial

Abstract

BackgroundLactococcus lactis JCM 5805 (LC-Plasma) is a unique lactic acid bacteria (LAB) which activates plasmacytoid dendritic cells (pDC). We aimed to evaluate the effect of LC-Plasma on dendritic cell (DC) activity and subjective indices of upper respiratory tract infections (URTI) and fatigue in athletes under high intensity exercise.MethodsWe conducted a randomized, placebo-controlled, double-blinded trial. Fifty-one male subjects belonging to a university sports club were randomized into placebo (n = 25) and LC-Plasma (n = 26) groups. Individuals ingested placebo capsules containing cornstarch or LC-Plasma capsules containing 100 billion cells of heat-killed LC-Plasma per day for 13 days. During the intervention period, subjects performed high intensity exercise according to their sports club training regime. Blood and saliva sampling were obtained at days 1 and 14, and physical conditions were recorded in a diary. We investigated expression of maturation markers on DCs, muscle damage and stress markers and used student’s t test adjusted by Bonferoni’s method for multiple comparison between groups. These data were presented as mean ± SD. We also investigated cumulative days of symptoms regarding infections and fatigue and used Chi-square test for comparison between groups. These data were presented as cumulative number.ResultsCD86 as maturation marker on pDC was significantly increased in the LC-Plasma group at day 14 (Placebo: 296 ± 70 vs. LC-Plasma: 365 ± 115; Mean Fluorescent Intensity; p = 0.013). Cumulative days of URTI were significantly lower in the LC-Plasma group (Placebo: URTI positive 56, URTI negative 256 vs. LC-Plasma: URTI positive 39, URTI negative 299; days; p = 0.028) and symptoms like sneeze or running nose were significantly lower in the LC-Plasma group (Placebo: Symptom positive 52, Symptom negative 258, vs. LC-Plasma: Symptom positive 36, Symptom negative 301; days; p = 0.032). Moreover, the cumulative days of fatigue were significantly fewer in the LC-Plasma group (Placebo: Symptom positive 128, Symptom negative 182, vs. LC-Plasma: Symptom positive 110, Symptom negative 225; days; p = 0.032). Markers of muscle damage and stress markers were not significantly different between groups.ConclusionWe consider that heat-killed LC-Plasma supplementation relieves morbidity and symptoms of URTI via activation of pDC and decreases fatigue accumulation during consecutive high intensity exercise in athletes. However, LC-Plasma ingestion did not affect markers of muscle damage and stress.Trial registrationUMIN-CTR, UMIN000020372. Registered 28 December 2015.

Effect of Daily Intake of Heat-Killed Lactobacillus plantarum HOKKAIDO on Immunocompetence: A Randomized, Double-Blind, Placebo-Controlled, Parallel-Group Study

“…Previous studies have suggested that for demonstrating the effect of probiotics, the intervention period should be >2 weeks [27][28][29]. Accordingly, it is suggested that at least 4 weeks of intake is necessary for observing the immunostimulatory effect of the HK-HOKKAIDO strain.…”

The immune system of athletes of different sports

“…The significant decrease in CD14 leukocytes was observed in swimmers and skaters. Komano et al [15] confirmed the significance of CD86 as a marker of sufficient immunity. Schlabe et al [16] demonstrated the improvement in metabolic and immunological parameters in HIV-infected patients who have undergone moderate endurance training.…”

Lactococcus lactis Strain Plasma Improves Subjective Physical State and Presenteeism: A Randomized, Open-Label Crossover Study among Healthy Office Workers

“…LC-Plasma reportedly stimulates human pDCs to reduce flu-like symptoms, such as runny noses and sore throats (Sugimura et al, 2013;Sugimura et al, 2015). LC-Plasma has also been reported to reduce accumulation of fatigue during consecutive high-intensity-exercise sessions in male athletes (Komano et al, 2018).…”