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

Abstract

Probiotic intake has been shown to improve certain physiological health indicators. We aimed to examine effects of Lactobacillus&nbsp;casei LTL1879, obtained from long-lived elderly volunteers, on blood biochemical, oxidative, and inflammatory markers and gut microbiota in twenty healthy, young volunteers. Volunteers were randomly divided into equal probiotic and placebo groups and changes in blood biochemical indicators, oxidative and inflammatory markers, and gut microbiota were examined after three weeks of probiotic intervention. The probiotic group's antioxidant levels were significantly enhanced post-intervention. Total antioxidant capacity (T-AOC) levels were significantly increased (p < 0.0001), while malondialdehyde (MDA) levels decreased (p < 0.05), and total superoxide dismutase (T-SOD) levels increased, but with no significant difference. In addition, Interleukin-10 (IL-10) and tumor necrosis factor-α (TNF-α) levels were significantly up-regulated and down-regulated (p < 0.05, respectively). Escherichia coli, Enterococcus, and Bacteroides expression was significantly reduced (p < 0.05), while Clostridium leptum, Bifidobacterium, and Lactobacillus expression increased (p < 0.05). Volunteer health status was quantified using principal components and cluster analysis, indicating that the probiotic group's overall score was higher than that of the placebo group. The results of this pilot study suggest L. casei LTL 1879 can significantly improve specific immune, oxidative, and gut microbiota characteristics related to health factors.

Keywords: Lactobacillus casei LTL1879; blood biochemical; gut microbiota; healthy young people; inflammation; oxidant; probiotics.

Figure 1

Schematic diagram indicating probiotic and placebo group intervention of the volunteers. Each group took the probiotic or placebo for three weeks. Blood samples of volunteers were collected at 0 and 3 weeks, and fecal samples were collected at 0, 2, 3, and 4 weeks.

Figure 2

Effects of LTL1879 on total superoxide dismutase (T-SOD) activity, malondialdehyde (MDA) levels, and total antioxidant capacity (T-AOC) activity in serum of volunteers. (A) Serum T-SOD activity of volunteers. (B) Serum MDA levels of volunteers. (C) Serum T-AOC activity of volunteers. (a) Serum T-SOD activity of volunteers in probiotics group. (b) Serum MDA levels of volunteers in probiotics group. (c) Serum T-AOC activity of volunteers in the probiotics group. Data are shown as means standard deviations (SD). Asterisks indicate significant differences (paired t-test, * p < 0.05, ** p < 0.01, **** p < 0.0001). n = 10 or n = 5 volunteers per group.

Figure 3

Effect of LTL1879 on inflammatory factors interleukin-10 (IL-10) and tumor necrosis factor-α (TNF-α). (A) Serum IL-10 levels in volunteers. (B) Serum TNF-α levels in volunteers. (a) Serum IL-10 levels in the probiotics group. (b) Serum TNF-α levels in the probiotics group volunteers. Data are shown as means standard deviations (SD). Asterisks indicate significant differences (paired t-test, * p < 0.05, ** p < 0.01). n = 10 or n = 5 volunteers per group.

Figure 4

Relative expression of fecal flora in volunteers. (A) Relative expression levels of 6 species of bacteria in the feces of volunteers (B) Relative expression levels of 6 species of bacteria in the feces of volunteers in the probiotics group. Colors ranging from blue to red indicate low to high expression. Asterisks indicate significant differences (paired t-test, compared with baseline value * p < 0.05, ** p < 0.01, **** p < 0.0001). n = 10 or n = 5 volunteers per group.

Figure 5

Correlation between the expression of Lactobacillus, oxidative, and inflammatory markers. Rank tests with Spearman’s correlation coefficient were used to assess correlations between Lactobacillus and oxidative markers (T-SOD, MDA, T-AOC), pro-inflammatory marker (TNF-α), and anti-inflammatory marker (IL-10). Asterisks indicate significant differences (Compared with baseline values, ** p < 0.01, *** p < 0.001, **** p < 0.0001). n = 10 volunteers per group.