Study On The Difference Of Adipokines Secreted By Adipose Tissue At Different Sites

Objective:Our previous research and other evidences have showed that the relationship between different parts of adipose tissue and obesity-related diseases such as insulin resistance(IR),type 2 diabetes(T2DM),and cardiovascular disease(CVD)are not exactly same.Visceral adipose tissue promotes these diseases development while subcutaneous adipose tissue protects.However,the specific mechanism is not yet clear.This study intends to investigate the differences of adipokines secreted by different regional adipose tissue and by GO and KEGG enrichment analysis provide a molecular basis for studying the relationship between different regional adipose tissue and obesity-related diseases.By GC-MS analysis to further study the biological function of human free fatty acids and provides biomarkers for the early diagnosis and prognosis of disease progression identified.Methods:Subcutaneous adipose tissue(SAT)and visceral adipose tissue(VAT)from six non-diabetic patients were collect and cultured with complete medium.The samples were divided into 2 groups:SAT group(6 cases),VAT group(6 cases).Extract the supernatant of the fourth day.RayBiotech AAH-ADI-G1 adipokine antibody chip was used to detected the expression of adipokines,and screened for the differential adipokines in the SAT and VAT groups.Gene Ontology(GO)and Kyoto encyclopedia of genes and genomes(KEGG)signal pathway were used to analysis the biologicacl process and fnction of differential adipokines.Gas chromatography-mass spectrometry(GC-MS)was used to analysis of the difference of free fatty acids(FFAs)profiles between SAT and VAT.Different types of FFAs in the supernatant of the fat group were separated and the relative percentages of various FFAs were determined,then the different expression of various FFAs in SAT and VAT were analyzed and compared.Results:1.62 kinds of adipokines were detected in the SAT and VAT complete culture.Comparative comparison of each adipokine in the SAT and VAT groups.IL-8,MCP-1,VEGF,sTNF RII,sTNF RI,Adipsin,IGFBP-1 adipokines were higher in VAT than that of SAT.(Pvalue<0.05,FC≥2 或 FC ≤ 0.5).2.GO analysis showed IL-8,MCP-1,VEGF,sTNF RII,sTNF RI,Adipsin,IGFBP-1 are related to 271 biological processes,such as bacterial molecular reaction,lipopolysaccharide response,and tumor necrosis factor response and so on.3.GO analysis showed IL-8,MCP-1,VEGF,sTNF RII,sTNF RI,Adipsin,IGFBP-1 are related to 12 cellular components,such as secretory granules,membrane regions,and membrane microdomains and so on.4.GO analysis showed IL-8,MCP-1,VEGF,sTNF RII,sTNF RI,Adipsin,IGFBP-1 are related to 22 molecular functions,such as cytokine receptor binding,cytokine activity,and sulfur compound binding and so on.5.KEGG signal pathway analysis showed IL-8,MCP-1,VEGF,sTNF RII,sTNF RI,Adipsin,IGFBP-1 are related to 20 signaling pathways,such as AGE-RAGE signaling pathways in diabetic complications,amyotrophic lateral sclerosis(ALS),and adipocytokine signaling and so on.6.A total of 13 fatty acid methyl esters were detected after complete methylation of supernatants of VAT and SAT.These are:Methyl isovalerate,Methyl octanoate,Methyl tetradecanoate,Methyl 13-methyl tetradecanoate,Methyl myristate,Methyl pentadecanoate,Pentadecanoic acid-14-Methyl methyl ester,9-hexadecamethyl carbonate,Methyl hexadecanoate,9-12-octadecadienoic acid(z,z)-methyl ester,9-octadecenoic acid(z)-Methyl ester,Methyl 9-octadecenoate,Methyl stearate.7.There was no difference in the relative component of various FFAs in SAT and VAT(P>0.05),but octanoic acid was highest in both VAT and SAT.Conclusions:1.IL-8,MCP-1,VEGF,sTNF RII,sTNF RI,Adipsin,IGFBP-1 adipokines were higher in VAT than that of SAT,suggesting that IL-8,MCP-1,VEGF,sTNF RII,sTNF RI,Adipsin,IGFBP-1 are closely related to the development of visceral obesity-related diseases.2.IL-8,MCP-1,VEGF,sTNF RII,sTNF RI,Adipsin,IGFBP-1 participate in the onset and development of diabetes and its complications through signal pathways,such as adipokine signaling pathway and AGE-RAGE signaling pathway.3.There were no differences in the component and relative percentage of FFAs between VAT and SAT,but the relative percentage of octanoic acid was highest in both VAT and SAT,suggesting that octanoic acid may play a major role in the development of FFAs-mediated diseases.