Soo Jeong Koh

Atherogenecity of LDL and Unfavorable Adipokine Profile in Metabolically Obese, Normal-weight Woman

Objective: The relationship of visceral adiposity with adipocytokines and low‐density lipoprotein (LDL) particle distribution and oxidation in Asian metabolically obese, normal‐weight (MONW) individuals has not been evaluated. We aimed to investigate the association between visceral adiposity and adipocytokines and cardiovascular disease (CVD) risk factors in MONW Korean women with normal glucose tolerance.

Genetic variation at the perilipin locus is associated with changes in serum free fatty acids and abdominal fat following mild weight loss.

Objective:Perilipin (PLIN) is a class of protein-coating lipid droplets in adipocytes. We aimed to examine the association between common single-nucleotide polymorphisms (SNPs) at PLIN locus with circulating free fatty acid (FFA) and abdominal fat distribution in response to weight loss.Methods:Non-diabetic/overweight-obese Koreans (n=177) participated in a 12-week calorie restriction (−300kcal/day) program. Seven SNPs (6209T>C, 10076C>G, 10171A>T, 11482G>A, 13042A>G, 13048C>T and 14995A>T), abdominal fat areas (visceral/subcutaneous fat areas at 1st lumbar and 4th lumbar levels), serum lipids, glucose, insulin, FFA, oxidized low-density lipoprotein (LDL) and urinary 8-epi-prostaglandin F2α (PGF2α) were examined.Results:Single-nucleotide polymorphisms 10076C>G/10171A>T showed the strongest positive linkage disequilibrium (LD) (D′=0.923, R 2=0.839, P<0.001) and SNPs11482G>A/14995A>T showed moderate positive LD (D′=0.824, R 2=0.578, P<0.001). Calorie restriction induced 4.6% weight loss with significant abdominal fat reduction. In response to weight loss, subjects with nCA/nCA haplotypes at SNPs 10076C>G/10171A>T showed greater reduction in FFA levels than those with CA/CA haplotype (CA/CA: C/C at SNP 10076 and A/A at SNP 10171, nCA: non-CA haplotype carrier). On the other hand, subjects with nGA/nGA haplotype at SNPs 11482G>A/14995A>T had increased FFA levels with a rapid loss in abdominal fat, whereas GA/GA haplotype carriers had reduction in FFA levels. These results still remained significant after adjusting for age, gender and BMI. Prostaglandin F2α and oxidized LDL were also more reduced in GA/GA haplotype carriers than in nGA haplotype carriers. This effect remained significant after adjusting for baseline level, age, gender and BMI. Paradoxically, nGA haplotype carriers had increased levels of urinary PGF2α after weight reduction.Conclusion:Fasting plasma FFA changes following a modest weight loss in overweight-obese subjects are influenced by the genetic variability at the PLIN locus. Furthermore, circulating FFA changes rather than body fat itself may determine changes in lipid peroxides such as urinary PGF2α and oxidized LDL.

The influence of the adiponectin gene on adiponectin concentrations and parameters of metabolic syndrome in non-diabetic Korean women

BACKGROUND Concentrations of adiponectin, the protein product of the adipocyte C1q and collagen-domain-containing (ADIPOQ) gene are associated with type 2 diabetes and coronary artery disease. We investigate the association of single-nucleotide polymorphisms (SNPs) in the ADIPOQ gene with adiponectin concentrations, and to parameters of metabolic syndrome. METHODS 867 unrelated, non-diabetic Korean women, 20 to 69 y, were genotyped for 8 SNPs in the ADIPOQ gene (-11391G>A, -11377C>G, H241P, Y111H, G90S, R221S, 45T>G, 276G>T). Adiponectin, a homeostasis model assessment of insulin resistance (HOMA-IR), and metabolic parameters were measured. RESULTS Carriers of genotype T/T at position 276 had significantly higher adiponectin concentrations than G/G carriers (P=0.005). Homozygous carriers of the TG haplotype (i.e., individuals who were T/T at 45 and G/G at 276) and heterozygous carriers of the TG haplotype (TG/X) had lower adiponectin concentrations than non-TG carriers (P<0.001). Significant associations between SNP at 276 and serum concentrations of triglyceride (P=0.013), insulin (P=0.013) and HOMA-IR (P=0.012) were found. The 45-276 haplotypes had associations identical to the 276G>T SNP. In subgroup analysis, subjects carrying the TG haplotype had significantly lower adiponectin concentrations than non-TG carriers in both normal weight (P<0.001) and overweight-obese (P=0.009) subgroups. The association of the TG haplotype with increasing insulin concentrations was significant among overweight-obese subjects (P=0.004), but was not significant among normal weight subjects. A similar association was found between the 45-276 haplotype and HOMA-IR. CONCLUSION There is a strong association of the adiponectin SNP276 genotypes and the adiponectin 45-276 haplotypes with circulating adiponectin concentrations in non-diabetic Korean women. In addition, this haplotype is associated with increased insulin concentrations and insulin resistance index only in overweight-obese individuals.

The association of SNP276G>T at adiponectin gene with circulating adiponectin and insulin resistance in response to mild weight loss

Objective:The purpose of this study was to determine whether common single nucleotide polymorphisms (SNPs) at the adiponectin (ADIPOQ) locus influence changes in circulating adiponectin and the features of insulin resistance in response to a weight loss intervention.Subjects:In total, 294 nondiabetic/overweight–obese Koreans participated in a clinical intervention study lasting 12 weeks involving a caloric reduction of −300kcal/day.Methods:Plasma adiponectin, blood lipids, glucose and insulin concentrations were measured at baseline and after weight loss. Insulin resistance was estimated by homeostasis model assessment insulin resistance (HOMA-IR) derived from fasting glucose and insulin concentrations. We genotyped for three SNPs, 45T>G, 276G>T and −11377C>G.Results:At baseline, HOMA-IR was significantly higher in GG homozygotes than in carriers of the T allele at SNP276G>T of the adiponectin gene (P<0.05). With regard to SNP45T>G and SNP −11377C>G, we did not find any genotype related differences in baseline levels of HOMA-IR and adiponectin. In the 45/276 haplotype test, homozygous for the TG haplotype had significantly lower concentrations of plasma adiponectin (P<0.05). After the 12-week weight loss intervention, the significant decreases in HOMA-IR (P<0.001) and increases in adiponectin (P<0.01) were observed in GG homozygotes at SNP276, which were not shown in carriers of the T allele. Furthermore, there was a significant difference in the decreases in HOMA-IR between the GG homozygotes and carriers of the T allele at SNP276 (P<0.05). Regarding SNP45T>G and SNP −11377C>G, there was no association between SNP45T>G and SNP −11377C>G and decreases in HOMA-IR. In the 45/276 haplotype test, there was a significant difference in changes of adiponectin levels among those with different haplotype combinations (P<0.05).Conclusion:The SNP276G>T of the ADIPOQ gene is associated with different responses of circulating adiponectin and insulin resistance to mild weight loss in overweight-obese subjects.

Comparison of low-fat meal and high-fat meal on postprandial lipemic response in non-obese men according to the -1131T>C polymorphism of the apolipoprotein A5 (APOA5) gene (randomized cross-over design).

Objective: The purpose of this study was to compare low-fat (LF) meal and high-fat (HF) meal on the postprandial lipemic responses according to the −1131T>C polymorphism of the APOA5 gene in a population usually consuming a LF diet and having a high frequency of the variant allele at the APOA5 −1131T>C SNP. Methods: This study was conducted using a cross-over design and 49 non-obese healthy men (42.8 ± 0.7 yrs, 23.9 ± 0.25 kg/m2) participated in the meal tolerance test. They were randomly assigned to consume one of two types of experimental enteral formulae (LF vs HF) with a seven-day interval. Blood samples were collected at 0, 2, 3, 4 and 6h after ingestion and analyzed for total and chylomicron TG, glucose, insulin and free fatty acid. Results: No differences were found in anthropometic parameter, calorie and macronutrient intakes and total energy expenditure between TT (n = 23) and TC + CC (n = 26) men. Fasting total TG were higher in TC + CC men than TT men, but fasting chylomicron TG were not significantly different between TT men and C carriers, TT subjects had no significant differences in postprandial responses of total TG and chylomicron TG and postprandial mean changes of chylomicron TG between LF and HF meal. On the other hand, C carriers had delayed peak time of total TG compared to TT subject and higher postprandial response and mean changes of chylomicron TG at HF meal compared to LF meal. Conclusion: The capacity to clear chylomicron-TG or hydrolyze TG might become a rate-limiting factor on HF diet in TC + CC men resulting in higher postprandial triglyceridemia. Therefore, HF diet for C carriers of the APOA5 gene may be one of important CVD risk factors.

The RANTES -403G > A promoter polymorphism in Korean men : association with serum RANTES concentration and coronary artery disease

In the present study we investigated the association of the RANTES (regulated upon activation, normal T-cell expressed and secreted) -28C>G and -403G>A promoter polymorphisms with the concentration of serum RANTES and CAD (coronary artery disease) in Korean men. We included 553 male CAD patients with (n=176) or without (n=377) Type 2 diabetes, aged 40-65 years with previous myocardial infarction ( approximately 50%) or angiographically confirmed CAD ( approximately 50%), and 416 aged-matched healthy male controls. The main outcome measures were the OR (odds ratio) of CAD risk and the serum RANTES concentration evaluated by sandwich ELISA. Although the RANTES -28C>G genotype had no significant association with CAD risk, the presence of the minor allele of the RANTES -403G>A single nucleotide polymorphism was associated with a lower risk of CAD {OR 0.70 [95% CI (confidence interval) 0.54-0.92], P=0.011} after adjusting for age, BMI (body mass index), cigarette smoking and alcohol consumption. Serum RANTES concentrations were significantly associated with the -403G>A genotype in controls (G/G: 44.7+/-3.3 ng/ml, G/A: 36.5+/-2.0 ng/ml, A/A: 28.7+/-2.5 ng/ml; P<0.001), non-diabetic CAD patients (G/G: 50.9+/-3.0 ng/ml, G/A: 42.2+/-2.6 ng/ml, A/A: 41.3+/-4.4 ng/ml; P<0.05) and diabetic CAD patients (G/G: 58.5+/-3.5 ng/ml, G/A: 49.6+/-4.1 ng/ml, A/A: 42.2+/-4.3 ng/ml; P<0.05); however, such associations were not observed in the subgroup of CAD patients taking lipid-lowering medication. Moreover, serum RANTES was positively correlated with C-reactive protein (r=0.289, P<0.001) and platelet counts (r=0.253, P<0.001). The results of the present study demonstrate that the RANTES -403A allele is associated with lower serum RANTES concentrations and consequently with reduced CAD risk.

Interleukin‐6 (IL‐6) –572C→G promoter polymorphism is associated with type 2 diabetes risk in Koreans

Objective  Increased levels of inflammatory markers, such as interleukin‐6 (IL‐6), are associated with type 2 diabetes (T2DM). We investigated the association of IL‐6 gene polymorphisms with T2DM and circulating levels of IL‐6 in Koreans.

Interleukin-6-572C>G polymorphism—association with inflammatory variables in Korean men with coronary artery disease

Growing evidence suggests that polymorphisms at position -174 and -572 in interleukin-6 (IL-6) gene are associated with various manifestations of atherosclerosis. We investigated the genotype effects of IL-6 -174 and -572 polymorphisms on circulating levels of inflammatory markers in Korean men with coronary artery disease (CAD). CAD patients were subdivided into 2 groups; those patients treated without lipid-lowering drug (LLD) (n = 173) and those treated with LLD (n = 353). No significant differences existed between the 2 groups in age, body mass index, blood pressure, serum glucose, alcohol consumption, cigarette smoking, and the proportions of antihypertensive and antiplatelet therapies. IL-6 - 572 C>G polymorphism was only observed in this population. In CAD patients not taking LLD, the G/G genotype of the -572C>G polymorphism was associated with greater concentrations of IL-6 (C/C: 4.1 +/- 0.8 pg/mL, C/G: 3.7 +/- 0.7, G/G: 12.4 +/- 6.6; P = 0.031), C-reactive protein (CRP) (C/C: 1.9 +/- 0.4 mg/dL, C/G: 2.7 +/- 0.8, G/G: 10.1 +/- 3.9; P = 0.002), fibrinogen (C/C: 334 +/- 6 mg/dL, C/G: 345 +/- 13, G/G: 429 +/- 38; P = 0.003), and oxidized low-density lipoprotein (ox-LDL) (C/C: 59 +/- 2 mg/dL, C/G: 55 +/- 3, G/G: 71 +/- 6; P = 0.041) than those with C/C or C/G. However, in the LLD group, no difference existed in circulating levels of IL-6, CRP, fibrinogen, and ox-LDL across the genotype after adjustment of age. This study suggests that circulating levels of IL-6 and its related proteins such as CRP and fibrinogen are associated with genotype at a promoter polymorphism (-572C>G) of the IL-6 gene in Korean men with CAD not taking LLD. LLD, mostly statin in this study, might reduce the exaggeration of G/G genotype-raising effect on inflammatory markers.

Association of serum RANTES concentrations with established cardiovascular risk markers in middle-aged subjects.

BACKGROUND RANTES (regulated upon activation, normal T cells expressed and secreted) is known to be related to an inflammatory part of the atherosclerotic process. We investigated the association of serum concentrations of RANTES with the risk of coronary artery disease (CAD) in a case-control study. METHODS One hundred fifty one CAD male patients aged 40 to 65 years and 151 age-matched healthy male controls were included and the main outcome measure was the odds ratio (OR) for CAD associated with increased levels of RANTES. RESULTS Serum levels of RANTES were higher in CAD patients when compared with controls (47.1+/-1.57 ng/mL vs 37.3+/-1.48; P<0.001). In addition, values in the second and top tertile of RANTES were associated with an increased OR for CAD when compared with values in the bottom tertile; OR for RANTES top tertile was 2.86 (95% CI, 1.53 to 5.34) in the age- and WHR-adjusted model and 3.23 (95% CI, 1.02 to 10.3) after the fully adjustment. Furthermore, there was a positive correlation of serum RANTES with acute phase proteins such as hs-CRP (r=0.310, P<0.001) and fibrinogen (r=0.333, P<0.001). RANTES concentrations also displayed a moderate correlation of WHR, triglyceride, HDL-cholesterol, interleukin-1 beta, interleukin-6, adiponectin, platelet and white blood cell counts. CONCLUSION In the present study, RANTES is associated with CAD risk in middle-aged subjects.