Anti-inflammatory effect of gallic acid-conjugated chitooligosaccharides in lipopolysaccharide-stimulated RAW 264.7 macrophages
Authors:   Deparment of Biochemistry, Faculty of Biology-Biotechnology, University of Science, Vietnam National University - Ho Chi Minh City,227 Nguyen Van Cu Street, Ward 4, District 5, Ho Chi Minh City, Vietnam, Bui Van-Hoai ,   Vietnam National University - Ho Chi Minh City, Linh Trung Ward, Thu Duc City, Ho Chi Minh City, Vietnam,   Ho Chi Minh City University of Industry and Trade (HUIT), 140 Le Trong Tan Street, Tay Thanh Ward, Tan Phu District, Ho Chi Minh City, Vietnam, Vo Hong-Tham N. ,   Deparment of Biochemistry, Faculty of Biology-Biotechnology, University of Science, Vietnam National University - Ho Chi Minh City,227 Nguyen Van Cu Street, Ward 4, District 5, Ho Chi Minh City, Vietnam,   Vietnam National University - Ho Chi Minh City, Linh Trung Ward, Thu Duc City, Ho Chi Minh City, Vietnam,   Ho Chi Minh City University of Industry and Trade (HUIT), 140 Le Trong Tan Street, Tay Thanh Ward, Tan Phu District, Ho Chi Minh City, Vietnam, Duong Thanh-Tuan ,   Deparment of Biochemistry, Faculty of Biology-Biotechnology, University of Science, Vietnam National University - Ho Chi Minh City,227 Nguyen Van Cu Street, Ward 4, District 5, Ho Chi Minh City, Vietnam,   Vietnam National University - Ho Chi Minh City, Linh Trung Ward, Thu Duc City, Ho Chi Minh City, Vietnam, Kim Se-Kwon ,   Department of Marine Science and Convergence Engineering, College of Science and Technology, Hanyang University,55 Hanyangdaehak-ro, Sangnok-gu, Ansan-si, Gyeonggi-do 11558, Korea, Ngo Dai-Nghiep ,   Deparment of Biochemistry, Faculty of Biology-Biotechnology, University of Science, Vietnam National University - Ho Chi Minh City,227 Nguyen Van Cu Street, Ward 4, District 5, Ho Chi Minh City, Vietnam,   Vietnam National University - Ho Chi Minh City, Linh Trung Ward, Thu Duc City, Ho Chi Minh City, Vietnam
Published: March 2024

The aim of the present study is to investigate the anti-inflammatory effect of gallic acid grafted onto COS chains (GA-COS), focusing on the reduction of nitric oxide production, downregulation of inflammatory signals such as inducible nitric oxide synthase (iNOS), gene expression of cytokines such as TNF-α, IL-1β, IL-6, and nuclear factor kappa B (NF-κB) signalling, including the p50 and p65 subunits. The anti-inflammatory effect is mediated through the reduction of nitric oxide production and downregulation of inflammatory proteins such as inducible nitric oxide synthase (iNOS), gene expression of cytokines like TNF-α, IL-1β, IL-6, and nuclear factor kappa B (NF-κB) signalling, including the p50 and p65 subunits. Target proteins were identified by western blot analysis with specific monoclonal antibodies. The levels of gene expression were determined by the RT-PCR method. The results demonstrate that GA-COS effectively reduces nitric oxide generation and downregulates iNOS protein and cytokine expression and NF-κB signalling in lipopolysaccharide (LPS) -induced RAW 264.7 cells. GA-COS exhibits significantly enhanced anti-inflammatory activity compared to the free chitooligosaccharide chain. This study lays the groundwork for future research to demonstrate that GA-COS holds significant potential as a novel compound for the prevention of inflammatory diseases.