Momordica charantia (Bitter Melon) reduces obesity-associated macrophage and mast cell infiltration as well as inflammatory cytokine expression in adipose tissues

• Published in: PloS one Vol. 8; no. 12; p. e84075
• Main Authors: Bao, Bin, Chen, Yan-Guang, Zhang, Lei, Na Xu, Yan Lin, Wang, Xin, Liu, Jian, Qu, Wei
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 17.12.2013; Public Library of Science (PLoS)
• Subjects: Adipose tissue; Adipose Tissue - metabolism; Adipose Tissue - pathology; Adiposity; Animal tissues; Animals; Body weight; Body weight gain; Cardiovascular diseases; Complications; Cytokines; Cytokines - blood; Cytokines - metabolism; Cytometry; Diabetes mellitus; Diet; Enzyme-linked immunosorbent assay; Epidemics; Flow cytometry; Heart diseases; High fat diet; House mouse; Infiltration; Inflammation; Inflammation Mediators - blood; Inflammation Mediators - metabolism; Insulin; Insulin Resistance; Interleukin 6; Kinases; Macrophages; Macrophages - metabolism; Macrophages - pathology; Male; Mast Cells - metabolism; Mast Cells - pathology; Metastases; Mice; Momordica charantia; Momordica charantia - chemistry; Monocyte chemoattractant protein 1; Obesity; Obesity - diet therapy; Obesity - etiology; Obesity - metabolism; Phenotype; Rodents; Serum levels; Tumor necrosis factor-α; Type 2 diabetes; Weight reduction; China
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0084075

Obesity is a world-wide epidemic disease that correlates closely with type 2 diabetes and cardiovascular diseases. Obesity-induced chronic adipose tissue inflammation is now considered as a critical contributor to the above complications. Momordica charantia (bitter melon, BM) is a traditional Chinese food and well known for its function of reducing body weight gain and insulin resistance. However, it is unclear whether BM could alleviate adipose tissue inflammation caused by obesity. In this study, C57BL/6 mice were fed high fat diet (HFD) with or without BM for 12 weeks. BM-contained diets ameliorated HFD-induced obesity and insulin resistance. Histological and real-time PCR analysis demonstrated BM not only reduced macrophage infiltration into epididymal adipose tissues (EAT) and brown adipose tissues (BAT). Flow cytometry show that BM could modify the M1/M2 phenotype ratio of macrophages in EAT. Further study showed that BM lowered mast cell recruitments in EAT, and depressed pro-inflammatory cytokine monocyte chemotactic protein-1 (MCP-1) expression in EAT and BAT as well as interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) expression in EAT. Finally, ELISA analysis showed BM-contained diets also normalized serum levels of the cytokines. In summary, in concert with ameliorated insulin resistance and fat deposition, BM reduced adipose tissue inflammation in diet-induced obese (DIO) mice.