Associations of free fatty acids with insulin secretion and action among African-American and European-American girls and women.
Ethnic differences in insulin secretion and action between African Americans (AAs) and European Americans (EAs) may influence mobilization of free fatty acids (FFAs). We tested the hypotheses that FFA concentrations would be associated with measures of insulin secretion and action before and during a glucose challenge test. Subjects were 48 prepubertal girls, 60 premenopausal women, and 46 postmenopausal women. Fasting insulin (insulin(0)), the acute insulin response to glucose (AIR(g)), the insulin sensitivity index (S(I)), basal and nadir FFA (FFA(0), FFA(nadir)), and nadir time (TIME(nadir)) were determined during an intravenous glucose tolerance test (IVGTT). Stepwise multiple linear regression (MLR) analysis was conducted to identify associations of FFA(0), FFA(nadir), and TIME(nadir) with ethnicity, age group, insulin measures, indexes of body composition from dual-energy X-ray absorptiometry, and measures of fat distribution from computed tomography scan. In this population, insulin(0) and AIR(g) were higher among AAs vs. EAs, whereas S(I) was lower, independent of age group. MLR analyses indicated that FFA(0) was best predicted by lean tissue mass (LTM), leg fat mass, ethnicity (lower in AAs), S(I), and insulin(0). FFA(nadir) was best predicted by FFA(0), age group, and intra-abdominal adipose tissue (IAAT). TIME(nadir) was best predicted by leg fat mass, AIR(g), and S(I). In conclusion, indexes of insulin secretion and action were associated with FFA dynamics in healthy girls and women. Lower FFA(0) among AAs was independent of insulin(0) and S(I). Whether lower FFA(0) is associated with substrate oxidation or risk for obesity remains to be determined.
Goree
Laura Lee T
LL
Department of Nutrition Sciences, University of Alabama at Birmingham, Birmingham, Alabama, USA. llt@uab.edu
Darnell
Betty E
BE
Oster
Robert A
RA
Brown
Marian A
MA
Gower
Barbara A
BA
D015502:Absorptiometry, Photon; D050154:Adiposity / Q000208:ethnology*; D000293:Adolescent; D000328:Adult; D001741:Black or African American; D000367:Age Factors; D000368:Aged; D000375:Aging / Q000208:ethnology / Q000378:metabolism; D002648:Child; D005230:Fatty Acids, Nonesterified / Q000097:blood*; D005260:Female; D005951:Glucose Tolerance Test; D006801:Humans; D007328:Insulin / Q000097:blood*; D007333:Insulin Resistance / Q000208:ethnology*; D016014:Linear Models; D008875:Middle Aged; D009765:Obesity / Q000208:ethnology* / Q000378:metabolism / Q000503:physiopathology; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D014481:United States; D044465:White People; D055815:Young Adult
D005230:Fatty Acids, Nonesterified; D007328:Insulin
Diabetes. 1996 Jun;45(6):742-8
8635647
Am J Clin Nutr. 2000 Mar;71(3):725-32
10702165
Am J Clin Nutr. 2003 Jun;77(6):1368-73
12791611
J Clin Invest. 2003 Apr;111(7):981-8
12671047
J Clin Endocrinol Metab. 1997 Jun;82(6):1923-7
9177407
J Clin Invest. 1990 May;85(5):1614-21
2159025
Obes Res. 1999 Sep;7(5):463-8
10509603
Obes Res. 1997 Jul;5(4):321-5
9285838
Diabetes. 1993 Nov;42(11):1567-73
8405696
Am J Physiol Endocrinol Metab. 2003 Jan;284(1):E7-12
12485807
Metabolism. 1997 Apr;46(4):400-5
9109843
Obes Res. 2001 Mar;9(3):224-8
11323449
J Clin Endocrinol Metab. 2002 May;87(5):2218-24
11994367
Diabetes Care. 2003 Jan;26 Suppl 1:S21-4
12502615
Metab Syndr Relat Disord. 2007 Spring;5(1):77-86
18370816
Am J Physiol. 1994 Apr;266(4 Pt 1):E600-5
8178981
Am J Clin Nutr. 2000 May;71(5):1138-46
10799376
JAMA. 2006 Apr 5;295(13):1549-55
16595758
Am J Physiol. 1999 Sep;277(3):E551-60
10484369
J Lipid Res. 1994 Feb;35(2):177-93
8169522
J Clin Endocrinol Metab. 2008 Nov;93(11):4547-51
18782873
Am J Physiol Regul Integr Comp Physiol. 2008 Oct;295(4):R1089-96
18685069
Int J Obes Relat Metab Disord. 1995 Apr;19(4):279-83
7627253
J Clin Endocrinol Metab. 2001 Jul;86(7):3022-6
11443162
Am J Clin Nutr. 1997 Sep;66(3):531-8
9280169
J Pediatr. 1996 Sep;129(3):440-3
8804335
Diabetes. 1999 Aug;48(8):1586-92
10426377
J Clin Endocrinol Metab. 2006 Oct;91(10):4099-106
16868062
Horm Metab Res. 2007 Oct;39(10):722-5
17952833
Diabetes. 2002 Feb;51 Suppl 1:S212-20
11815482
Am J Clin Nutr. 1999 Jul;70(1):13-20
10393133