Co-administration of the prebiotic 1-kestose and the paraprobiotic Lactiplantibacillus plantarum FM8 in magellanic penguins promotes the activity of intestinal Lactobacillaceae and reduces the plc gene levels encoding Clostridium perfringens toxin

Abstract

Despite the well-known potential health benefits of prebiotics and non-viable probiotics (paraprobiotics) in various animal species, research regarding their use in penguins is scarce. Our study aimed to investigate the impact of a combined administration of prebiotics and paraprobiotics (referred to here as "parasynbiotics") on the gut microbiome and overall health of Magellanic penguins (Spheniscus magellanicus). The parasynbiotics consisted of 1-kestose, which is a fructooligosaccharide comprising sucrose and fructose, and heat-killed Lactiplantibacillus plantarum FM8, isolated from pickled vegetables. It was administered to eight penguins aged <3 years (Young-group) and nine penguins aged >17 years (Adult-group) for 8 weeks. Results from 16S rRNA sequencing revealed that compared to baseline, parasynbiotic administration significantly decreased the relative abundance of intestinal Clostridiaceae_222000 in both groups and significantly increased that of Lactobacillaceae in the Young-group. Quantitative real-time polymerase chain reaction revealed a significant decrease in the plc gene levels encoding alpha-toxin of Clostridium perfringens in the Young-group after parasynbiotic administration (P=0.0078). In the Young-group, parasynbiotic administration significantly increased the plasma levels of total alpha-globulin (P=0.0234), which is associated with inflammatory responses. Furthermore, exposure of dendritic cells to heat-killed L. plantarum FM8 promoted the secretion of interleukin 10, a major anti-inflammatory cytokine. Overall, parasynbiotic administration enhanced the activity of gut Lactobacillaceae, decreased the levels of C. perfringens and its toxin encoding plc gene, and reduced inflammatory response in penguins. These results provide novel insights into the potential benefits of parasynbiotics for improving penguin health.

Keywords: 1-kestose; Lactiplantibacillus plantarum FM8; parasynbiotics; penguin’s health.

Fig. 1.

Alpha and beta diversity plots before (Baseline) and after daily parasynbiotic administration (Week 8) in Young- and Adult-groups. (A) Box-plot corresponding to the Shannon index (alpha diversity). (B) Box-plot corresponding to the Chao1 index (alpha diversity). Bars represent the median (interquartile range, 25–75%). Statistical significance was determined using Kruskal–Wallis test followed by Dunn’s multiple comparisons test, *P<0.05. (C) Principal coordinate analysis (PCoA) of the weighted UniFrac distance (beta diversity). Circles and squares represent individual mice.

Fig. 2.

(A) The mean relative abundance of each family of penguin fecal microbiome detected by 16S rRNA sequence analysis before (Baseline) and after daily parasynbiotic administration (Week 8). (B) Mean relative abundance of Clostridiaceae_222000, Lactobacillaceae, and Peptostreptococcaceae_256921 before (baseline) and after parasynbiotic administration (week 8). Circles represent individual penguins, and bars represent mean ± SEM. Statistical significance was determined using Wilcoxon matched-pairs signed rank test, *P<0.05; ns=not significant.

Fig. 3.

Changes in the plc levels in penguin fecal microbiome detected by qPCR before (Baseline) and after parasynbiotic administration (Week 8) in Young- (A) and Adult-groups (B). Comparison of baseline levels of plc levels in penguin fecal microbiome between Young- and Adult-groups (C). Circles represent individual penguins, and bars represent mean ± SEM. Statistical significance was determined using Wilcoxon matched-pairs signed rank test, **P<0.01; ns=not significant.

Fig. 4.

Penguin alpha-globulin levels after 8 weeks of parasynbiotic administration when compared to baseline for Young- (A) and Adult-groups (B). Comparison of the total serum levels of alpha-globulin in the Young- and Adult-penguins at baseline (C). Circles represent individual penguins, and bars represent mean ± SEM. Statistical significance was determined using the Wilcoxon matched-pairs signed rank test, *P<0.05; ns=not significant.

Fig. 5.

Interleukin-10 levels produced in stimulated bone marrow-derived dendritic cells were measured. The following groups were assessed: cells exposed to the vehicle (NC), heat-killed Lactiplantibacillus plantarum FM8 (FM8), or lipopolysaccharide (LPS). Circles represent individual penguins, and bars represent mean ± SEM. Statistical significance was determined using the Kruskal–Wallis test, *P<0.05.