Effects of Yiqi Gubiao pills on visceral fat accumulation and metabolic inflammation in mice with COPD
Objective To investigate the effects of Yiqi Gubiao pills on visceral fat accumulation,white fat brown-ing and metabolic inflammation in chronic obstructive pulmonary disease(COPD)mice,and to explore the possible mech-anism.Methods Thirty C57BL/6 male mice were randomly divided into the control group,COPD group and Yiqi Gu-biao pills group,with 10 mice in each group.Mice in the COPD group and Yiqi Gubiao pills group were treated with inha-lation of cigarette smoke exposure combined with intraperitoneal injection of cigarette smoke extract to establish COPD models.Yiqi Gubiao pills group was given 200 µL of Yiqi Gubiao pills solution once a day for 2 weeks after modeling.Mice in the control group and COPD group were given equal volume of normal saline through intragastric administration.Lee's index and lipid-body ratio of each group were measured.Lung tissues and white and brown adipose tissues were tak-en after death for pathological observation.Western blotting was used to detect the protein expression levels of browning-re-lated indicators of white adipose tissues[silent information regulator 1(SIRT1),peroxisome proliferator-activated recep-tors γ(PPARγ),uncoupling protein 1(UCP1),peroxisome proliferator activated receptor γ coactivator-1α(PGC-1α),PR domain-containing 16(PRDM16)]and inflammatory response-related indicators[tumor necrosis factor-α(TNF-α),interleukin 6(IL-6)and and IL-8].UCP1 relative fluorescence intensity in white and brown adipose tissues was detected by immunofluorescence method,the mRNA expression levels of TNF-α,IL-6 and IL-8 in white adipose tissues was detect-ed by real-time fluorescence quantitative PCR method,and serum levels of IL-6,IL-8 and TNF-α were detected by ELI-SA.Results In the COPD group,the pulmonary alveolar wall was slightly thickened,the alveolar interval was widened and inflammatory cells infiltrated.Compared with the COPD group,the above-mentioned manifestations of pulmonary tis-sues of Yiqi Gubiao pills group were reduced.Compared with the control group,the volume of adipose cells in the white and brown adipose tissue of the COPD group increased,and the vacuoles in the cells increased.Compared with the COPD group,the fat droplets in white and brown adipose tissues of the Yiqi Gubiao pills group decreased,showing browning.Compared with the blank control group,Lee's index,lipid-body ratio and serum levels of IL-6,IL-8 and TNF-α in-creased,the relative expression levels of TNF-α,IL-6 and IL-8 protein and mRNA in the white adipose tissues increased,the relative expression levels of SIRT1,PPARγ,UCP1,PGC-1α and PRDM16 proteins in white adipose tissue and the rel-ative fluorescence intensity of UCP1 in white and brown adipose tissues decreased in the COPD group(all P<0.05).Com-pared with the COPD group,Lee's index,lipid-body ratio and serum levels of IL-6,IL-8 and TNF-α decreased,and the relative expression levels of TNF-α,IL-6 and IL-8 protein and mRNA in white adipose tissue decreased,the relative ex-pression levels of SIRT1,PPARγ,UCP1,PGC-1α and PRDM16 proteins in white adipose tissues and the relative fluores-cence intensity of UCP1 in white and brown adipose tissues increased in Yiqi Gubiao pills group(all P<0.05).Conclusion Yiqi Gubiao pills can reduce visceral fat accumulation and metabolic inflammatory response in COPD mice,and the mechanism may be related to promoting the browning of white fat by targeting SIRT1/PPARγ/UCP1 pathway.