The protective mechanism of a novel polysaccharide from Lactobacillus-fermented Nostoc commune Vauch. on attenuating cadmium-induced kidney injury in mice.

A novel polysaccharide (NCVP-F) from Lactobacillus -fermented Nostoc commune Vauch. was obtained to investigate its underlying mechanism in cadmium-induced kidney injury. Results indicated that in comparison with NCVP, NCVP-F with lower molecular weight of 365.369 kDa, exhibited higher mole percentage of Man and Glc-UA, whereas slightly lower mole percentage of other monosaccharides. NCVP-F is a α-pyran polysaccharide similar to NCVP. Meanwhile, NCVP-F can more effectively alleviate hepatorenal injury (ALT, AST, TG, BUN and SCr) and kidney tissue lesions in Cd-injured mice model by increasing antioxidant enzyme activity (SOD, GSH and GSH-Px), inhibiting cytokines levels (IL-6, IL-1β, TNF-α and IL-18). In addition, NCVP-F effectively inhibited apoptosis proteins (Bax, cytochrome c , a-caspase-9 and a-caspase-3) and enhanced anti-apoptotic protein (Bcl-2) probably via activating PI3K/AKT/mTOR pathway in the Cd-injury kidney. Furthermore, 16S rRNA sequencing results indicated that NCVP-F better enriched Lachnospiraceae , reduced Muribaculaceae , Alloprevotella and Blautia to regulate Cd-induced gut microbiota disorders, which was probably down-regulated 7 pathways including apoptosis and lipopolysaccharide biosynthesis, and up-regulated 63 pathways, such as carbohydrate metabolism and lipid metabolism. This study suggested that applying functional NCVP-F prepared by biotransformation with low molecular weight might be more beneficial. [Display omitted] • A novel polysaccharide (NCVP-F) from Lactobacillus -fermentated N. commune has low M W. • NCVP-F exhibits better effect than NCVP on attenuating Cd-induced kidney injury. • NCVP-F may inhibit apoptosis by PI3K/AKT/mTOR pathway in Cd-injury kidney. • NCVPs enriched different gut microbiota involved in different metabolic pathways. [ABSTRACT FROM AUTHOR]