Meta-Analysis: Randomized Trials of Lactobacillus plantarum on Immune Regulation Over the Last Decades

Abstract

Lactobacillus (L.) plantarum strains, belong to lactic acid bacteria group, are considered indispensable probiotics. Here, we performed meta-analysis to evaluate the regulatory effects of L. plantarum on the immunity during clinical trials. This meta-analysis was conducted by searching across four most common literature databases, namely, Cochrane Central Register of Controlled Trials, Web of Science, Embase, and PubMed. Clinical trial articles that met the inclusion and exclusion criteria were analyzed by Review Manager (version 5.3). p-value < 0.05 of the total effect was considered statistically significant. Finally, total of 677 references were retrieved, among which six references and 18 randomized controlled trials were included in the meta-analysis. The mean differences observed at 95% confidence interval: interleukin (IL)-4, −0.48 pg/mL (−0.79 to −0.17; p < 0.05); IL-10, 9.88 pg/mL (6.52 to 13.2; p < 0.05); tumor necrosis factor (TNF)-α, −2.34 pg/mL (−3.5 to −1.19; p < 0.05); interferon (IFN)-γ, −0.99 pg/mL (−1.56 to −0.41; p < 0.05). Therefore, meta-analysis results suggested that L. plantarum could promote host immunity by regulating pro-inflammatory and anti-inflammatory cytokines.

Probiotic improves symptomatic and viral clearance in Covid19 outpatients: a randomized, quadruple-blinded, placebo-controlled trial

“…Inspired by the success of the cited randomized trial 38 but under the hypothesis that a cocktail of strains could better represent a natural ingestion of endophytic-type bacteria than a single strain, we chose a formula containing three different L. plantarum strains and one P. acidilactici (all of them originally isolated from humans on a vegetable-rich diet and not consuming probiotics). However, it must be stressed that existing evidence indicates probiotic immune effects are strain-specific, 4 , 12 and effect from one strain cannot be directly extrapolated to other strains, even if from the same species (e.g. L. plantarum ), until clinical trials with relevant endpoints are conducted.…”

Evaluation of IR Biotyper for Lactiplantibacillus plantarum Typing and Its Application Potential in Probiotic Preliminary Screening

“…L. plantarum strains have diverse phenotypes and genotypes that facilitate a metabolic flexibility that allow them to colonize a variety of environments, including the human gastrointestinal tract ( Pretzer et al, 2005 ; Marco et al, 2010 ; Fidanza et al, 2021 ). There have been reports indicating their potential beneficial effects on humans ( Molenaar et al, 2005 ; Klarin et al, 2008 ; Siezen et al, 2010 ; Lewis-Mikhael et al, 2020 ; Zhao et al, 2021 ). Its excellent adaptability, extensive industrial applicability and powerful influence on human and animal physiology have made L. plantarum a microorganism of great interest to the academic community.…”

Multi-Probiotic Lactobacillus Supplementation Improves Liver Function and Reduces Cholesterol Levels in Jeju Native Pigs

“…Lactobacillus spp. augment the production of immune response-related cytokines, such as TNF-α, IL-1β, IL-6, IL-12, and IFN-γ, which trigger a physiological immune response [ 29 ]. Lactobacillus spp.…”