Effects of Litchi chinensis fruit isolates on prostaglandin E(2 )and nitric oxide production in J774 murine macrophage cells

BACKGROUND: Litchi chinensis is regarded as one of the 'heating' fruits in China, which causes serious inflammation symptoms to people. METHODS: In the current study, the effects of isolates of litchi on prostaglandin E(2 )(PGE(2)) and nitric oxide (NO) production in J774 murine macrophage cells were investigated. RESULTS: The AcOEt extract (EAE) of litchi was found effective on stimulating PGE(2 )production, and three compounds, benzyl alcohol, hydrobenzoin and 5-hydroxymethyl-2-furfurolaldehyde (5-HMF), were isolated and identified from the EAE. Benzyl alcohol caused markedly increase in PGE(2 )and NO production, compared with lipopolysaccharide (LPS) as positive control, and in a dose-dependent manner. Hydrobenzoin and 5-HMF were found in litchi for the first time, and both of them stimulated PGE(2 )and NO production moderately in a dose-dependent manner. Besides, regulation of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) mRNA expression and NF-κB (p50) activation might be involved in mechanism of the stimulative process. CONCLUSION: The study showed, some short molecular compounds in litchi play inflammatory effects on human.