Relation Between Serum Adipocyte Fatty Acid-binding Protein And Islet Beta Cell Function In Individuals With Different Glucose Tolerance

Objective: Adipocyte fatty acid-binding protein (A-FABP) is anew-found adipocytokine, which regulates of adipocyte differentiation andplays an important role in fat and fatty acid metabolism, meanwhile it affectsadipose tissue, liver and muscle insulin sensitivity. The present study wasdesigned to investigate the changes of serum A-FABP level and therelationship between serum A-FABP level and body mass index(BMI), bloodpressure, blood glucose, blood lipid, HOMA-insulin resistance index(HOMA-IR), and insulin levels in the population with different glucosetolerance.Methods:1Subjects: A total of120subjects (69male, average52.01±11.84years,51female, average55.98±8.92years) were recruited from January2012toDecember2012at The third hospital of Hebei medical university. Subjectswith type1diabetes or specific diabetes, endocrine disorders, severecardiovascular disease, gastrointestinal disease, acute or chronic inflammationwere excluded from this study. They were divided into3groups according to75g oral glucose-tolerance-test (OGTT), including normal glucose tolerance(NGT), impaired glucose regulation (IGR) which includes impaired glucosetolerance (IGT) and impaired fasting glucose (IFG), and type2diabetes(T2DM). The T2DM group was divided into2subgroups by BMI according tothe guidelines of the Prevention and treatment adiposity in China, whichincluded group A (non-obese subjects, n=30, BMI<28kg/m2), and group B,(obese subjects, n=32, BMI≥28kg/m2). This study was approved by theInstitute Review Board of Hebei Medical University. A written informedconsent was obtained from all subjects involved before participation in the study.2Methods: General clinical data of each patient was recorded in detail,including Sex, Age, Height, Weight [calculated body mass index (BMI)], waistcircumference， thigh circumference, systolic blood pressure (SBP), anddiastolic blood pressure (DBP). All subjects were fasted overnight for≥8h,venous blood samples were collected, concentrations of triglyceride (TG),total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C),low-density lipoprotein cholesterol (LDL-C), fasting plasma glucose (FPG)and fasting insulin (FINS) were measured. Glycosylated hemoglobin (HbA1C)was measured using a DCA2000analyzer (Bayer Medical, Germany).Homeostasis model assessment-insulin resistance (HOMA-IR) was obtainedby calculation: AUCINS=1/4S0+1/2S30+3/4S60+S120+1/2S180, AUCGLU=1/4S0+1/2S30+3/4S60+S120+1/2S180, HOMA-IR=FPG (mmol/L)×FINS (mIU/L)/22.5, HOMA-β=20×FINS/(FPG–3.5). The Intra and inter-assay coefficientsof variation (CV) were <9%and <15%, respectively.3Satistical analysis: Quantitative data were expressed as means±SD.Comparison between4groups was performed by one-way analysis of variance(ANOVA). The Pearson correlation analysis was used for univariate analysisbetween A-FABP concentrations and various anthropometric and biochemicalmeasures. Multiple regression analysis for multivariate analysis. Statisticalanalyses were done by SPSS Software (V13.0, SPSS Inc, USA). P values <0.05were considered statistically significant.Results:1The levels of serum A-FABP were significantly higher in T2DMsubjects than those of IGR and NGT subjects (P<0.01). Compared with NGTgroup, fasting serum A-FABP levels were significantly increased in IGRgroup (P<0.01).2The level of serum A-FABP was significantly higher in T2DM obesesubjects than T2DM non-obese subjects (P<0.01).3Serum A-FABP level was correlated positively with BMI、WC、HC、UA、TC、TG、FPG、2hPG、HbA1C、AUCGLUand HOMA-IR (r=0.295, P<0.01; r=0.217, P<0.05; r=0.226, P<0.05; r=0.611, P=0.000; r=0.194,P<0.05; r=0.338, P<0.01; r=0.386, P=0.000; r=0.518, P=0.000; r=0.448,P=0.000; r=0.505, P=0.000; r=0.345, P=0.000). There was no correlationbetween LDL-C、HDL-C、SBP、DBP、FINS、AUCINS、HOMA-β(all P>0.05).Multiple regression analysis showed that BMI, HbA1C and UA wereindependent related factors for serum A-FABP levels. Y=66.385+4.792×BMI+8.213×HbA1C+0.095×UA.Conclusions:The level of A-FABP is associated with obesity, insulin resistance,abnormal glucose and lipid metabolism, measurement of serum A-FABPconcentrations might be useful for diagnosis and prevention of type2diabetes.