# Effect of PPAR-α agonist on adipokines expression in rats fed with high-fat diet LI yan#, HUANG bin, CHENG hua, LIANG zhen, LIU shan-ying

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1 PPAR-α # PPAR-α SD SD 6 4 RT-PCR?? mrna FFA TG HOME-IR FFA 2.37± ± ±0.34 mmol/l p<0.001 TG 0.48± ± ±0.07 mmol/l p<0.001 HOME-IR 12.30± ± ±1.27 p<0.001 TNF-α mrna 1.726± ± ±0.382 p ± ± ±0.130 p AGT 1 AT1R 6 IL-6 mrna p>0.05 PPAR-α PPAR-α Effect of PPAR-α agonist on adipokines expression in rats fed with high-fat diet LI yan#, HUANG bin, CHENG hua, LIANG zhen, LIU shan-ying Department of Endocrinology, The Second Affiliated Hospital of Sun Yat-sen University, Guangzhou , China Abstract Objective To explore the influence of PPAR-α agonist fenofibrate on adipokines expression in high-fat diet fed SD rats and its relationship to insulin resistance (IR). Methods Rats were allocated into three groups(n=10): high fat diet, high fat diet plus treatment with fenofibrate, and normal diet group. Animals were sacrificed after 4-week follow-up. Plasma lipids, fasting plasma insulin, free fatty acids (FFA) and insulin sensitivity were detected. RT-PCR was used to semi-quantify adipokines expression in brown fat. Results High-fat diet was

2 associated with increase in plasma level of lipids, free fatty acid (FFA), fast plasma insulin, HOMA-IR, increased expression of TNF-α and decreased adiponectin expression in adipose tissues. Fenofibrate reversed these changes. Conclusion PPAR-α agonist fenofibrate may play a role in improving high fat diet induced lipid abnormalities and insulin sensitivity, which were associated with down-regulation of TNF-α expression and up-regulated adiponectin expression in adipose tissues. Key words PPAR-α agonist, adipokines, free fatty Acid,insulin resistance # Corresponding author Tel: , liyan @yahoo.com

3 IR FFA TG [1] -a TNF-α -6 IL-6 AGT 1 AT1 mrna SD g g/100g Wt Wt 23.5 g/100g mg.kg -1.d ml kg -1 d g 20 FFAs Randox Linco research inc. HOMA-IR 2 100mg 2ml 80 mrna RT-PCR -actin Pubmed TNF-α adiponcetin cdna Primer 5.0

4 1. TNF-α 5 -CCAACAAGGAGGAGAAGTTCC-3 5 -TGGGAGTAGATAAGGTACAGC C-3 249bp β-actin 5 -CTATCGGCAATGAGCGGTTC-3 5 -CTTAGGAGTTGGGGGTGGCT-3 734bp β-actin 5 - TGGTCGTACCACTGGCATTGTG TGACCTGACCGTCAGGCATCTC bp 3. adiponcetin 5 - ATCACTCAGCATTCAGCG TAGG ATACACTTGGAGCCAGACTTGG bp β-actin IL-6 4. AGT 5 -ACC CCT TTC ATC TCC TCT ACT-3 5 -GGG TGT CTG GCT GCT GCT TCC-3 488bp β-actin 5 -CTA TCG GCA ATG AGC GGT TC-3' 5 -CTT AGG AGT TGG GGG TGG CT-3'; 734bp 5. AT1R 5 -TGT TTT ATG GCT TTC TGG GG-3 5 -CAG TGG CTT TGC TCC AAT TT-3 418bp β-actin AGT Trizol Invitrogen RNA A 260 RNA RT RNA 1µg 5 5µl dntp TaKaRa 10mmol/l 5µl TaKaRa 2µl RNA

5 TaKaRa 25U MMLV Promega 200U RNA 25µl Biometra T GRADIENT 37 1h 95 5min MMLV PCR 4 PCR RT 5µl 10 PCR 5µl MgCl 2 23mM 3µl dntp 2.5mmol/l 4µl 20µM 1µl β-actin 1µl Taq TaKaRa 2U 50µl Biometra T GRADIENT TNF-α β-actin 95 5min 94 1min 57 1min min IL-6 adiponcetin β-actin 95 5 Taq PCR PCR PCR 5µl 2 5V/cm SYBR Green AlphaImager 2200 /β-actin mrna 3 ±s LSD P 0.05 HOMA IR 10 FFA TG HOMA-IR 1 1 SD 4 (n=10) (n=10) (n=10) F P FBG mmol/l 4.94± ± ± FINS mmol/l 0.911± ± ±

6 TG mmol/l 0.30±4.3 E ± ±7.2 E FFA mmol/l 1.59± ± ± HOMR-IR 5.03± ± ± P<0.05 P TNF-α mrna P<0.05 mrna P<0.05 AGT 1 AT1R 6 IL-6 mrna P> (n=10) (n=10) (n=10) P TNF-α 0.713± ± ± ± ± ± IL AGT 1.489± ± ± AT1R 1.995± ± ± P<0.05 P / [2] TG FFA -a peroxisome proliferator-activated receptor-a PPARa [3] SD HOMA-IR

7 FFA TG mrna mrna FFA FFA [4] PPARa [5] TNF-a IL-6 TNF-a LPL TNF-a TNF-α κb NF-κB IKK IRS-1 [6] TNF-a TNF-α mrna TNF-α IL-6 SOCS SOCS IRS-1 IRS-1 [7] IL-6 mrna IL-6 IL-6 [8] SOCS - RAS II [9] II 1 mrna RAS mrna

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