title: IFN-γ secretion in gut of Ob/Ob mice after vertical sleeve gastrectomy and its function in weight loss mechanism.
abstract: Vertical sleeve gastrectomy (VSG) is becoming more and more popular among the world. Despite its dramatic efficacy, however, the mechanism of VSG remains largely undetermined. This study aimed to test interferon (IFN)-γ secretion n of mesenteric lymph nodes in obese mice (ob/ob mice), a model of VSG, and its relationship with farnesoid X receptor (FXR) expression in the liver and small intestine, and to investigate the weight loss mechanism of VSG. The wild type (WT) mice and ob/ob mice were divided into four groups: A (WT+Sham), B (WT+VSG), C (ob/ob+Sham), and D (ob/ob+VSG). Body weight values were monitored. The IFN-γ expression in mesenteric lymph nodes of ob/ob mice pre- and post-operation was detected by flow cytometry (FCM). The FXR expression in the liver and small intestine was detected by Western blotting. The mouse AML-12 liver cells were stimulated with IFN-γ at different concentrations in vitro. The changes of FXR expression were also examined. The results showed that the body weight of ob/ob mice was significantly declined from (40.6±2.7) g to (27.5±3.8) g on the 30th day after VSG (P<0.05). At the same time, VSG induced a higher level secretion of IFN-γ in mesenteric lymph nodes of ob/ob mice than that pre-operation (P<0.05). The FXR expression levels in the liver and small intestine after VSG were respectively 0.97±0.07 and 0.84±0.07 fold of GAPDH, which were significantly higher than pre-operative levels of 0.50±0.06 and 0.48±0.06 respectively (P<0.05). After the stimulation of AML-12 liver cells in vitro by different concentrations of IFN-γ (0, 10, 25, 50, 100, and 200 ng/mL), the relative FXR expression levels were 0.22±0.04, 0.31±0.04, 0.39±0.05, 0.38±0.05, 0.56±0.06, and 0.35±0.05, respectively, suggesting IFN-γ could distinctly promote the FXR expression in a dose-dependent manner in comparison to those cells without IFN-γ stimulation (P<0.05). It was concluded that VSG induces a weight loss in ob/ob mice by increasing IFN-γ secretion of mesenteric lymph nodes, which then increases the FXR expression of the liver and small intestine.
authors.affiliation: Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
authors.forename: Jin-Peng
authors.initials: JP
authors.lastname: Du
authors.affiliation: Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
authors.forename: Geng
authors.initials: G
authors.lastname: Wang
authors.affiliation: Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
authors.forename: Chao-Jie
authors.initials: CJ
authors.lastname: Hu
authors.affiliation: Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
authors.forename: Qing-Bo
authors.initials: QB
authors.lastname: Wang
authors.affiliation: Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
authors.forename: Hui-Qing
authors.initials: HQ
authors.lastname: Li
authors.affiliation: Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
authors.forename: Wen-Fang
authors.initials: WF
authors.lastname: Xia
authors.affiliation: Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
authors.forename: Xiao-Ming
authors.initials: XM
authors.lastname: Shuai
authors.affiliation: Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
authors.forename: Kai-Xiong
authors.initials: KX
authors.lastname: Tao
authors.affiliation: Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China.
authors.forename: Guo-Bin
authors.initials: GB
authors.lastname: Wang
authors.affiliation: Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430022, China. xiazefeng@sina.com.
authors.forename: Ze-Feng
authors.initials: ZF
authors.lastname: Xia
mesh_terms: D000818:Animals; D001835:Body Weight; D002460:Cell Line; D005743:Gastrectomy / Q000379:methods; D015870:Gene Expression; D022781:Hepatocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D007371:Interferon-gamma / Q000096:biosynthesis* / Q000378:metabolism / Q000494:pharmacology; D007421:Intestine, Small / Q000187:drug effects* / Q000378:metabolism; D008099:Liver / Q000187:drug effects* / Q000378:metabolism; D008198:Lymph Nodes / Q000187:drug effects* / Q000378:metabolism; D008643:Mesentery / Q000187:drug effects / Q000378:metabolism; D051379:Mice; D008820:Mice, Obese; D009765:Obesity / Q000378:metabolism / Q000473:pathology / Q000601:surgery*; D018160:Receptors, Cytoplasmic and Nuclear / Q000819:agonists* / Q000235:genetics / Q000378:metabolism; D015431:Weight Loss; D000099150:Receptor, Farnesoid X-Activated
chemical_list: D007371:Interferon-gamma; D018160:Receptors, Cytoplasmic and Nuclear; D000099150:Receptor, Farnesoid X-Activated
keywords: farnesoid X receptor; interferon-gamma; obesity; vertical sleeve gastrectomy; weight loss