The probiotic strain is Lactobacillus casei LTL 1879, isolated from the faeces of healthy centenarians.
Writing in Nutrients, the researchers from Jiangnan University and Guangxi University said that the strain had significantly improved certain immune, oxidative, and gut microbiome characteristics.
The pilot study involved 20 healthy adults between 20 and 35 years old who were randomised into the intervention and placebo group.
The intervention group had to take two grams of freeze-dried probiotic powder with warm water on an empty stomach every morning.
Changes in their oxidative, inflammatory markers and gut microbiota were measured to determine the effects of the probiotic.
“Probiotics obtained from long-lived elderly individuals have attracted much attention in recent years because of their excellent probiotic effects.
“However, reports mostly focused on evaluating the effects of probiotics on specific groups such as patients and the elderly, and few studies have proven the effects of probiotics on healthy, young individuals.
“In this study, short-term probiotic intervention was conducted on healthy, young volunteers, and it was found that L. casei LTL1879 obtained from long-lived elderly individuals had improved specific oxidative, immune, and intestinal microbial characteristics,” said the researchers.
Reduced oxidative stress
Findings showed that supplementation of Lactobacillus casei LTL 1879 had significantly reduced oxidative stress and total antioxidant capacity.
In the intervention group, the level of malondialdehyde – a biomarker of oxidative stress – had significantly decreased by 19.28 per cent. In contrast, no significant changes were seen in the placebo group.
When comparing between men and women, the reduction in malondialdehyde was significantly higher in men than in women.
In men, malondialdehyde levels had dropped by 25 per cent, while the decrease was lower at 13.50 per cent in women.
On the other hand, total antioxidant capacity in the intervention group had increased significantly by 52.70 per cent by the end of the study. Again, no significant changes were seen in the placebo group.
In addition, the amount of superoxide dismutase (SOD) – the enzyme that serves as an antioxidant – had increased slightly in the intervention group, while that of the placebo group had decreased. These changes, however, were not statistically significant.
Changes in inflammatory markers
The probiotic has also showed significant anti-inflammatory effects.
In the intervention group, the amount of anti-inflammatory cytokine, IL-10, had significantly went up by 8.10 per cent, while no changes were seen in the placebo group.
On the other hand, the pro-inflammatory cytokine, TNF-alpha, had decreased by 32.38 per cent in the intervention group and was down by 14.49 per cent in the placebo group.
The researchers said these results showed that the probiotic supplementation could improve the immunity of young healthy individuals.
Changes in gut microbiome
Significant changes were seen in the gut microbiota of the intervention group.
For example, in the intervention group, the number of E. coli had started to drop after two weeks into the study and further went down by 33.54 per cent by the end of the study.
The amount of E. coli rebounded one week after the probiotic supplementation had ended.
On the other hand, the number of beneficial bacteria, namely Bifidobacterium and Lactobacillus had significantly increased by 27.32 per cent and 44.27 per cent respectively within the second week of the study.
The rise became even more notable during the third week of intervention, with Bifidobacterium and Lactobacillus up 74.09 per cent and 107.20 per cent respectively.
The number of Bifidobacterium and Lactobacillus remained higher than the baseline value one week after the intervention had stopped.
In fact, the researchers noticed that there was a significant positive correlation between Lactobacillus expression and antioxidant activities.
“The results of this pilot study suggest L. casei LTL1879 can significantly improve specific immune, oxidative, and gut microbiota characteristics related to health factors.
“However, the number of participants in this study is relatively small, and the effect of exploring strains on individuals was limited.
“Therefore, it is necessary to expand the intervention population, select targeted models, and extend the intervention time in future studies, to further determine the function of LTL1879,” the researchers said.
This study was funded by the National Natural Science Foundation of China.
A Pilot Study of the Effect of Lactobacillus casei Obtained from Long-Lived Elderly on Blood Biochemical, Oxidative, and Inflammatory Markers, and on Gut Microbiota in Young Volunteers
Authors: Li-Hua Mei et al