Elucidating the effects of microbe-derived glucans on the gut microbiota and the immune system of zebrafish

We present a holistic picture of soybean-induced changes in the intestine of juvenile zebrafish and the effect of yeast beta glucan through a transcriptomic approach. Dietary soybean altered the expression of specific GTP binding genes which are known to initiate inflammatory responses in the intestinal tissue. The intestinal barrier function appears to be affected by the modulation of mucin genes and genes linked to junction proteins. Furthermore, the inclusion of soybean meal affected metabolic genes that are related to oxidative stress and genes related to lipid metabolism, namely arl4ca and elovl6 in the intestinal tissue. Genes that counter inflammation were also upregulated in the soybean fed group. Our study also explains the plausible effect of yeast beta glucan on the intestinal barrier through regulation of immune responses and autophagy, and strengthening of the mucosal barrier. Our findings indicate a subdued inflammation in juvenile zebrafish fed soybean meal and a strengthened mucosal barrier in the fish fed yeast beta-glucan.