Effect of acute physiological hyperinsulinemia on gene expression in human skeletal muscle in vivo.
This study was undertaken to test the hypothesis that short-term exposure (4 h) to physiological hyperinsulinemia in normal, healthy subjects without a family history of diabetes would induce a low grade inflammatory response independently of glycemic status. Twelve normal glucose tolerant subjects received a 4-h euglycemic hyperinsulinemic clamp with biopsies of the vastus lateralis muscle. Microarray analysis identified 121 probe sets that were significantly altered in response to physiological hyperinsulinemia while maintaining euglycemia. In normal, healthy human subjects insulin increased the mRNAs of a number of inflammatory genes (CCL2, CXCL2 and THBD) and transcription factors (ATF3, BHLHB2, HES1, KLF10, JUNB, FOS, and FOSB). A number of other genes were upregulated in response to insulin, including RRAD, MT, and SGK. CITED2, a known coactivator of PPARalpha, was significantly downregulated. SGK and CITED2 are located at chromosome 6q23, where we previously detected strong linkage to fasting plasma insulin concentrations. We independently validated the mRNA expression changes in an additional five subjects and closely paralleled the results observed in the original 12 subjects. A saline infusion in healthy, normal glucose-tolerant subjects without family history of diabetes demonstrated that the genes altered during the euglycemic hyperinsulinemic clamp were due to hyperinsulinemia and were unrelated to the biopsy procedure per se. The results of the present study demonstrate that insulin acutely regulates the levels of mRNAs involved in inflammation and transcription and identifies several candidate genes, including HES1 and BHLHB2, for further investigation.
Coletta
Dawn K
DK
Division of Diabetes, Department of Medicine, University of Texas Health Science Centre, San Antonio, TX, USA. richardsond2@uthscsa.edu
Balas
Bogdan
B
Chavez
Alberto O
AO
Baig
Muhammad
M
Abdul-Ghani
Muhammad
M
Kashyap
Sangeeta R
SR
Folli
Franco
F
Tripathy
Devjit
D
Mandarino
Lawrence J
LJ
Cornell
John E
JE
Defronzo
Ralph A
RA
Jenkinson
Christopher P
CP
D000328:Adult; D004396:Coloring Agents; D030541:Databases, Genetic; D004032:Diet; D005260:Female; D015870:Gene Expression / Q000502:physiology*; D005947:Glucose / Q000378:metabolism; D015309:Glucose Clamp Technique; D006801:Humans; D006946:Hyperinsulinism / Q000235:genetics*; D007091:Image Processing, Computer-Assisted; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D007249:Inflammation / Q000139:chemically induced / Q000473:pathology; D008297:Male; D018482:Muscle, Skeletal / Q000378:metabolism*; D020411:Oligonucleotide Array Sequence Analysis; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000235:genetics
D004396:Coloring Agents; D012333:RNA, Messenger; D005947:Glucose