Pro-inflammatory effects of a litchi protein extract in murine RAW264.7 macrophages. (4th May 2016)

• Record Type: Journal Article
• Authors: Wang, Xiaoli; Hu, Xiaorong; Yan, Huiqing; Ma, Zhaocheng; Deng, Xiuxin
• Is Part Of: Horticulture research. Volume 3(2016)
• Publication Date: 2016-05-04
• Subjects: Secondary metabolism; Horticulture -- Research -- Periodicals; 635.072
• DOI: 10.1038/hortres.2016.17
• Languages: English
• ISSNs: 2052-7276

Abstract

Abstract: It has been observed that the consumption of litchi often causes symptoms characterized by itching or sore throat, gum swelling, oral cavity ulcers and even fever and inflammation, which significantly impair the quality of life of a large population. Using the RAW264.7 cell line, a step-by-step strategy was used to screen for the components in litchi fruits that elicited adverse reactions. The adverse reaction fractions were identified by mass spectrometry and analyzed using the SMART program, and a sequence alignment of the homologous proteins was performed. MTT tests were used to determine the cytotoxicity of a litchi protein extract in RAW264.7 macrophages, and real-time PCR was applied to analyze the expression of inflammatory genes in the RAW264.7 cells treated with lipopolysaccharide or the litchi protein extract. The results showed that the litchi water-soluble protein extract could increase the production of the pro-inflammatory mediators IL-1β, iNOS and COX-2, and the anti-inflammatory mediator HO-1 in the RAW264.7 cell line. The 14-3-3-like proteins GF14 lambda, GF14 omega and GF14 upsilon were likely the candidate proteins that caused the adverse effects. Abstract : Tropical fruit crops: Why the litchi makes you itchy A laboratory study of immune cells has revealed key proteins involved in a widespread allergic response to litchi fruits. The litchi (lychee) is an increasingly popular fruit, but in some consumers causes an allergic reaction resulting in itching, swelling and even breathing difficulties. A Chinese team led by Zhaocheng Ma of Huazhong Agricultural University, Wuhan, separated litchi flesh into chemical fractions. They tested one fraction containing water-soluble proteins against immune cells known as macrophages, cultured from mice. The litchi proteins stimulated the macrophages to produce several molecules with known involvement in inflammatory responses. Further analysis of the litchi fraction revealed multiple members of a regulatory protein family which are known, from other organisms, to have inflammatory effects. These proteins are therefore considered most likely responsible for allergic reactions to litchi.