Anti-Obesity Activity of Guava Branch Extract in the Co-Culture System of Adipocytes and Macrophages

Obesity has become a prevalent health problem worldwide. In this study, the phytochemicals in guava branches were identified by using liquid chromatography-quadrupole time-of-flight mass spectrometry (LC-Q-TOF-MS). Also, the anti-obesity and anti-inflammatory activities of guava branch extracts were investigated in 3T3-L1 adipocytes and RAW264.7 macrophages. The guava branches were extracted with 100% ethanol (E100), and water at 95C or 80C. A total of 15 compounds, including catechin, gallic acid, and quercetin, were tentatively identified in the guava branches. The cell viability was determined by a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay and no cytotoxic effect was observed for all tested extracts in both cell lines. In addition, the E100 extract greatly suppressed lipid accumulation in the 3T3-L1 adipocytes. Treatment with E100 extract showed the most effective inhibition of nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated macrophages. We also found that E100 extract markedly decreased NO production by about 78% compared to the LPS-only treated group in the co-culture system of adipocytes and macrophages. Therefore, these results suggest that guava branch extracts may be useful for preventing obesity.