Bombyx mori pupae protects against chronic kidney disease by affecting intestinal microflora via moricin B

Bombyx moripupae (BMP) may have protective effects against chronic kidney disease (CKD) by improving intestinal microflora via antimicrobial peptides. The antimicrobial peptidesin BMP were analyzed by high-performance liquid chromatography (HPLC) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) after E. coli induction. CKD patients were assigned into BMP intervention (BG, 2-gram daily) and placebo (CG) groups. Lipid- and redox-related biochemical indices were measured. After 3-month treatment, BMP improved kidney function and controlled the blood levels of urinal protein, blood urea nitrogen (BUN) and creatinine. BMP improved lipid profile and redox system of CKD patients by affecting serum levels of Total cholesterol (TC), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C), and cystatin-C (Cys-C), myeloperoxidase (MPO), malondialdehyde (MDA), nitric oxide (NO) and superoxide dismutase (SOD) (p<0.05). BMP consumption reduced the amounts of Enterobacter, Enterococcus, Bacterioides and Clostridium, and increased the amounts of Lactobacillus and Bifidobacterium(p<0.05). On the other hand, moricin B was increased in BMP after E. coli induction. The peptide inhibited the growth rate of Enterobacter, Enterococcus and Bacterioides and promoted the growth of Clostridium, Lactobacillus and Bifidobacterium. The results of kidney injury mouse model showed that as the main component of BMP, moricin B treatment reduced the serum levels of creatinine, BUN, and urinary protein, and improved pathological kidney lesionsand microflora composition. Thus, BMP protected against chronic kidney disease by improving intestinal microflora via moricin B.