The Role of Exogenous Hydrogen Sulfide in Free Fatty Acids Induced Inflammation in Macrophages

• Main Authors: Zhu-lin Luo, Jian-dong Ren, Zhu Huang, Tao Wang, Ke Xiang, Long Cheng, Li-jun Tang
• Format: Article
• Language: English
• Published: Cell Physiol Biochem Press GmbH & Co KG 2017-07-01
• Series: Cellular Physiology and Biochemistry
• Subjects: Exogenous Hydrogen Sulfide; Free Fatty Acids; Inflammation; Macrophages
• Online Access: http://www.karger.com/Article/FullText/479405
• ISSN: 1015-8987; 1421-9778

Background: This study aimed to investigate whether exogenous hydrogen sulfide (H2S) can protect the RAW264.7 macrophages against the inflammation induced by free fatty acids (FFA) by blunting NLRP3 inflammasome activation via a specific TLR4/NF-κB pathway. Methods: RAW264.7 macrophages were exposed to increasing concentrations of FFA for up to 3 days to induce FFA-induced inflammation. The cells were pretreated with NaHS (a donor of H2S) before exposure to FFA. Cell viability, cell apoptosis, TLR4, NF-κB, NLRP3 inflammasome, IL-1β, IL-18 and cleaved caspase-3 expression were measured by a combination of MTT assay, ELISA, and immunoblotting. Results: H2S attenuated FFA-induced cell apoptosis, and reduced the expression of NLRP3, ASC, pro-caspase-1, caspase-1, IL- 1β, IL-18 and caspase-3. In addition, H2S inhibited the FFA-induced activation of TLR4 and NF-κB. Furthermore, NLRP3 inflammasome activation was regulated by the TLR4 and NF-κB pathway. Conclusion: The present study demonstrated for the first time that H2S appears to suppress FFA-induced macrophage inflammation and apoptosis by inhibiting the TLR4/ NF-κB pathway and its downstream NLRP3 inflammasome activation. Thus H2S might possess potential in the treatment of diseases resulting from FFA overload like insulin resistance and type diabetes.