Study On The Anti-inflammatory And Lipid-lowering Activities Of Novel Chimeric Peptide

Objective Acne was treated by combining the N-terminal of HPA3NT3（where Lys in position 13 was replaced by Asn）and the C-terminal antibacterial peptide HAG of GLP-1（32–36）amide pentapeptide after amino replacement.Methods The minimal inhibitory concentration（MIC）was measured using the broth dilution method to evaluate HAG’s antibacterial activity.HAG’s cytotoxicity was determined using water-soluble tetrazolium salt（WST-1）.Interleukin-8（IL-8）expression in human immortalized keratinocytes（HaCaT）cells stimulated by Propionibacterium acnes and treated with HAG was measured by Enzyme-linked immunosorbent assay（ELISA）.IL-8 and toll-like receptor 2（TLR2）expression was detected using real-time reverse transcriptase polymerase chain reaction（qRT-PCR）to analyze HAG’s anti-inflammatory effect in vitro.The total RNA was extracted using SiO₂ nanoparticles.Oil red O staining was used to detect the intracellular lipid drop of Sebaceous Gland Cell Line（SZ95）,and ELISA was used to detect triglyceride levels.Hematoxylin-eosin（HE）staining was used to evaluate ear edema induced by Propionibacterium acne in mice.Results The MIC of HAG in Propionibacterium acnes was 6.3μg/m L,and 50μg/mL of HAG showed cytotoxicity.HAG significantly reduced TLR2 and IL-8 expression in HaCaT cells.Oil red O staining showed that the lipid distribution of HAG-treated SZ95and triglyceride secretion decreased.HAG reduced ear swelling induced by Propionibacterium acnes.Conclusion HAG has anti-bacterial and anti-inflammatory effects,excellent hypolipidemic function,and low cytotoxicity.Further development of HAG as a treatment is necessary.