Lactobacillus plantarum DR7 improved upper respiratory tract infections via enhancing immune and inflammatory parameters: A randomized, double-blind, placebo-controlled study.
- 2019-06
- Journal of Dairy Science 102(6)
- H. Chong
- N. A. A. Yusoff
- Y. Hor
- L. Lew
- M. Jaafar
- S. Choi
- M. Yusoff
- N. Wahid
- M. F. I. L. Abdullah
- Norzila Zakaria
- Kee-Leong Ong
- Yong-Ha Park
- M. Liong
- PubMed: 30954261
- DOI: 10.3168/jds.2018-16103
Abstract
The aims of this study were to investigate the effects of Lactobacillus plantarum DR7 isolated from bovine milk against upper respiratory tract infections (URTI) and elucidate the possible mechanisms underlying immunomodulatory properties. The DR7 strain (9 log cfu/d) was administered for 12 wk in a randomized, double-blind, and placebo-controlled human study involving 109 adults (DR7, n = 56; placebo, n = 53). Subjects were assessed for health conditions monthly via questionnaires, and blood samples were evaluated for cytokine concentrations, peroxidation and oxidative stress, and gene expression in T cells and natural killer (NK) cells. The administration of DR7 reduced the duration of nasal symptoms (mean difference 5.09 d; 95% CI: 0.42-9.75) and the frequency of URTI (mean difference 0.32; 95% CI: 0.01-0.63) after 12 and 4 wk, respectively, compared with the placebo. The DR7 treatment suppressed plasma proinflammatory cytokines (IFN-γ, TNF-α) in middle-aged adults (30 to 60 yr old), while enhancing anti-inflammatory cytokines (IL-4, IL-10) in young adults (<30 yr old), accompanied by reduced plasma peroxidation and oxidative stress levels compared with the placebo. Young adults who received DR7 showed higher expression of plasma CD44 and CD117 by 4.50- and 2.22-fold, respectively, compared with the placebo. Meanwhile, middle-aged adults showed lower expression of plasma CD4 and CD8 by 11.26- and 1.80-fold, respectively, compared with the placebo, indicating less T-cell activation. In contrast, both young and middle-aged adults who received DR7 showed enhanced presence of nonresting and mature NK cells compared with those who received the placebo. We postulate that DR7 alleviated the symptoms of URTI by improving inflammatory parameters and enhancing immunomodulatory properties.
Keywords: Lactobacillus plantarum DR7; T cells; mucosal integrity; natural killer cells; upper respiratory tract infection.
Research Insights
| Supplement | Health Outcome | Effect Type | Effect Size |
|---|---|---|---|
| Lactobacillus plantarum DR7 | Increased Anti-Inflammatory Cytokine Levels | Beneficial | Moderate |
| Lactobacillus plantarum DR7 | Reduced Duration of Nasal Symptoms | Beneficial | Moderate |
| Lactobacillus plantarum DR7 | Reduced Frequency of Upper Respiratory Tract Infections | Beneficial | Small |
| Lactobacillus plantarum DR7 | Reduced Proinflammatory Cytokines in Middle-aged Adults | Beneficial | Large |
| Lactobacillus plantarum KABP™-061 | Increased Anti-Inflammatory Cytokine Levels | Beneficial | Moderate |
| Lactobacillus plantarum KABP™-061 | Reduced Duration of Nasal Symptoms | Beneficial | Moderate |
| Lactobacillus plantarum KABP™-061 | Reduced Frequency of Upper Respiratory Tract Infections | Beneficial | Small |
| Lactobacillus plantarum KABP™-061 | Reduced Plasma Proinflammatory Cytokines | Beneficial | Moderate |
| Lactobacillus plantarum Rosell-1012 | Increased Anti-Inflammatory Cytokine Levels | Beneficial | Moderate |
| Lactobacillus plantarum Rosell-1012 | Reduced Duration of Nasal Symptoms | Beneficial | Moderate |
| Lactobacillus plantarum Rosell-1012 | Reduced Plasma Proinflammatory Cytokines | Beneficial | Moderate |
| Lactobacillus plantarum Rosell-1012 | Reduced Upper Respiratory Tract Infections Frequency | Beneficial | Small |
| Lactobacillus plantarum UALp-05 | Increased Anti-Inflammatory Cytokine Levels | Beneficial | Moderate |
| Lactobacillus plantarum UALp-05 | Reduced Frequency of Upper Respiratory Tract Infections | Beneficial | Small |
| Lactobacillus plantarum UALp-05 | Reduced Plasma Proinflammatory Cytokines in Middle-Aged Adults | Beneficial | Moderate |
| Lactobacillus plantarum UALp-05M | Increased Anti-Inflammatory Cytokine Levels | Beneficial | Moderate |
| Lactobacillus plantarum UALp-05M | Reduced Duration of Nasal Symptoms | Beneficial | Moderate |
| Lactobacillus plantarum UALp-05M | Reduced Frequency of Upper Respiratory Tract Infections | Beneficial | Small |
| Lactobacillus plantarum UALp-05M | Reduced Inflammatory Cytokines | Beneficial | Moderate |
| Lactobacillus plantarum VPro 10 | Increased Anti-Inflammatory Cytokine Levels | Beneficial | Moderate |
| Lactobacillus plantarum VPro 10 | Reduced Duration of Nasal Symptoms | Beneficial | Moderate |
| Lactobacillus plantarum VPro 10 | Reduced Frequency of Upper Respiratory Tract Infections | Beneficial | Small |
| Lactobacillus plantarum VPro 10 | Reduced Plasma Proinflammatory Cytokines in Middle-Aged Adults | Beneficial | Moderate |