Anti-aging Effect And Molecular Mechanism Of Sturgeon Bladder Collagen Peptide Based On Multi-omics

Acipenser schrenckii has unique dietary characteristics,economic and ecological value,and is widely cultivated around the world.However,as the amount of sturgeon breeding increases yearly,a large amount of processing waste has caused serious waste of resources and environmental pollution.Sturgeon swim bladder is one of the main wastes of sturgeon processing,its dried product is also known as fish maw.It has the functions of invigorating the kidney and nourishing essence,nourishing muscles and veins,and delaying aging in Chinese medicine records.However,its efficacy and molecular mechanism have not been confirmed by modern scientific research,resulting in its market application is still controversial.This article uses sturgeon swim bladder as raw material to prepare collagen peptides(CPs),and uses high-throughput multi-omics technology to study the effect and its molecular mechanism of collagen peptides on delaying the aging of Caenorhabditis elegans and the effects of regulating the gut microbes in mice.The main content and results are as follows:(1)Using sturgeon swim bladder collagen as raw material,CPs were prepared by bio-directed enzymatic hydrolysis.The average molecular weight of CPs was 552 Da as measured by gel permeation chromatography.Among them,54.35%of peptides were distributed in 180-500 Da,and 30.34%of peptides were distributed in 500-1000Da,free amino acids accounted for 4.67%;using De novo peptideomics sequencing technology,a total of 407 peptides in CPs were identified,with a typical collagen amino acid sequence(G-X-Y);the C-terminal of the peptide chain was K or R,which was consistent with the trypsin digestion site;through the comparison with the NCBI database,the coverage of the first 100 sequences on the?1 and?2 chains of type I collagen of Sturgeon was 68.4%and 64.8%,respectively.(2)CPs(25 mg/mL)could prolong the average lifespan of wild-type C.elegans by 22.60%,increas body length by 24.41%,increas sinusoidal movement frequency by25.00%,and inhibit lipofuscin accumulation by 15.08%;after H₂O₂ oxidative stress 48h,CPs increased the survival rate by 40.06%;CPs reduced the accumulation of ROS by 22.80%,increased the activities of superoxide dismutase,catalase and glutathione S-transferase by 52.30%,62.40%and 135.70%,and reduced the content of peroxidation product malondialdehyde by 60.80%,and inhibited the cell apoptosis rate by 44.50%;CPs could increase the survival rate by 64.70%and enhance the barrier function by 38.70%under the condition of high osmotic pressure of Na Cl for 12 h.This showed that CPs could enhance the ability of environmental stress and delay the aging process by improving the body's antioxidant capacity and barrier function of C.elegans.(3)The use of transcriptomics technology found that there were 1610 differentially expressed genes in C.elegans treated with 25 mg/mL CPs for 12 days,of which 234were up-regulated and 1376 were down-regulated;GO analysis revealed that the functions of differentially expressed genes were mostly enriched in cellular processes,metabolic process and biological regulation process,combined function and catalytic activity,as well as membrane,cell and organelle composition;through KEGG analysis,it was found that CPs could directly or indirectly increase stress by regulating the MAPK signaling pathway,IIS signaling pathway,lipid metabolism and other pathways to directly or indirectly improve stress ability,inhibit abnormal protein aggregation and increase oleic acid levels,thereby extending the lifespan of C.elegans.(4)Through the 12-month feeding experiment of C57BL/6J mice,it was found that no toxic and side effects were found when the added amount of CPs was 4.86 g/kg bw·d or the replacement amount was 2.39 g/kg bw·d;using intestinal microbiome technology found that,compared with the CK group,the beneficial bacteria Bacilli,and Clostridiales were significantly enriched in the CPs add(?4.86 g/kg bw·d)group.Campilobacterota,Deferribacterota,Tuzzerella,Helicobacter and other pathogenic bacteria were significantly enriched in the CPs replace(>2.39 g/kg bw·d)group;the enrichment of functional pathways in the CPs addition group(4.86 g/kg bw·d)was significantly higher than that in the CK group,including transcription,transportation and catabolism,digestive system,amino acid metabolism,biosynthesis of other secondary metabolites,carbohydrate metabolism,energy metabolism,nucleotide metabolism and biodegradation pathways of xenobiotics.This indicates that CPs could enhance the immune and metabolic functions of the host,protect the health of the body,and delay the aging of the body by improving the body's defenses,digestive system and the effective degradation of foreign toxins.