Hye Soon Park

Socioeconomic Status in Relation to Obesity and Abdominal Obesity in Korean Adults: A Focus on Sex Differences

Objective: We examined the relationship between income and education level with BMI and waist circumference to provide further understanding of the relationship between socioeconomic status and obesity and to identify the presence of sex differences.

Elevated alanine aminotransferase levels predict mortality from cardiovascular disease and diabetes in Koreans

OBJECTIVE Metabolic syndrome is associated with increased cardiovascular morbidity and mortality. Nonalcoholic fatty liver disease (NAFLD) is closely associated with metabolic syndrome. This study investigated the relationship between elevated alanine aminotransferase (ALT) levels, as a proxy marker of NAFLD, and death from cardiovascular disease (CVD) or diabetes in a Korean population. METHODS The study population consisted of 37,085 patients who underwent health examinations at the Health Promotion Center of the Asan Medical Center, Seoul, Korea, in 2000 and 2001. Individuals with viral hepatitis or alcoholic liver disease were excluded from the study. The relationship between baseline ALT levels and CVD- or diabetes-related mortality was determined for a median period of 5.0 years. RESULTS A total of 407 deaths occurred during the follow-up period, with 91 deaths resulting from CVD or diabetes. The multivariate relative risk (RR) and 95% confidence interval (CI) for CVD- or diabetes-related mortality in patients with ALT levels >40IU/L were 2.26 (1.22-4.19). The multivariate RR and 95% CI for CVD- or diabetes-related mortality in patients with the highest quartile of ALT levels (> or =31IU/L) were 2.28 (95% CI: 1.02-5.08) when the lowest quartile (< or =15IU/L) was used as a reference. CONCLUSION Our findings demonstrate that elevated ALT levels are independently associated with increased CVD- or diabetes-related mortality in Koreans. Thus, elevated ALT levels, as a marker for NAFLD, may serve as a surrogate predictor of CVD- or diabetes-related mortality among the Korean population.

Dietary patterns and the metabolic syndrome in Korean adolescents: 2001 Korean National Health and Nutrition Survey.

The presence of metabolic syndrome in children and adolescents represents a high-risk state that conveys an increased risk of metabolic disease (1,2). The importance of the role of dietary patterns cannot be overemphasized because of the relation to metabolic disease. Although previous studies show that some dietary patterns are related to the risk of the metabolic syndrome (3–6), these studies focus on adults and were rarely conducted on children or adolescents in a nationally based survey. Therefore, the aim of this study was to identify dietary patterns and to examine the association between dietary patterns and the metabolic syndrome in Korean adolescents. Although studies on the Korean population may yield unique results primarily due to the ethnic homogeneity inherent to the Korean population with very little genetic diversity, the results tend to be applicable to other countries as well. The 2001 Korean National Health and Nutrition Survey, a cross-sectional and nationally representative survey, was conducted from November to December 2001. A stratified, multistage, probability sampling design was used, with selection made from sampling units. Weights indicating the probability of being sampled were assigned to each participant, which enabled the results to represent the entire Korean population. A total of 12,441 individuals participated in the Health Interview Survey, which included a 24-h dietary intake recall. …

Association between low SIRT1 expression in visceral and subcutaneous adipose tissues and metabolic abnormalities in women with obesity and type 2 diabetes

AIMS To assess the importance of adipose tissue sirtuin 1 (SIRT1) in the regulation of whole-body metabolism in humans with obesity and type 2 diabetes. METHODS In total, 19 non-diabetic obese women, 19 type 2 diabetic women undergoing gastric bypass surgery, and 27 normal-weight women undergoing gynecological surgery (total 65 women) were enrolled. Their anthropometric variables, abdominal fat distribution and metabolic parameters, serum adiponectin concentrations, and SIRT1 mRNA and protein and adiponectin mRNA expressions in visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) were measured. RESULTS SIRT1 mRNA levels in VAT and SAT were similar and these levels were suppressed in obese and type 2 diabetic women compared to normal-weight subjects. These decreases in SIRT1 expression were observed in both adipocytes and non-fat cells. There was a strong association between adipose tissue SIRT1 mRNA and protein levels. Adipose SIRT1 expression correlated inversely with HOMA-IR and other insulin resistance-related parameters. Adipose SIRT1 and adiponectin mRNA expression correlated very strongly and positively. SIRT1 mRNA level in VAT correlated inversely with visceral obesity whereas its expression in SAT correlated negatively with body mass index. CONCLUSIONS Adipose tissue SIRT1 may play a key role in the regulation of whole body metabolic homeostasis in humans. Downregulation of SIRT1 in VAT may contribute to the metabolic abnormalities that are associated with visceral obesity.

Effect of weight reduction on metabolic syndrome in Korean obese patients.

The Third Report of the National Cholesterol Education Program Adult Treatment Panel III emphasized the importance of management of the metabolic syndrome. However, little information is available about the effect of weight reduction on the metabolic syndrome in obese patients among Koreans. A longitudinal clinical intervention study from the 12-week of weight reduction program, including life style modification and adjuvant appetite suppressants, in 78 obese persons was performed. Anthropometry and metabolic risk factors were measured before and after weight reduction. Visceral (VAT), subcutaneous (SAT), and total adipose tissue (TAT) on abdomen were determined by CT scan. Moderate decrease in weight (9.3%) induced significant reduction of waist circumference, systolic and diastolic blood pressure, and triglyceride. Weight reduction also resulted in significant decrease in total cholesterol, LDL-C, uric acid, fasting insulin, and HOMA score. The subjects with metabolic syndrome showed more improvements of metabolic components than those without metabolic syndrome through weight reduction. The reductions of visceral-subcutaneous fat ratio (VSR) and waist circumference were observed as for the predictable variables related to the improvement of metabolic component and insulin resistance in Korean obese patients.

Colorectal neoplasms in relation to non-alcoholic fatty liver disease in Korean women: a retrospective cohort study.

Background and Aim:  Metabolic syndrome has been associated with an increased risk for colorectal cancer. Non‐alcoholic fatty liver disease (NAFLD) is regarded as a hepatic manifestation of metabolic syndrome. We investigated whether NAFLD is associated with colorectal neoplasms in Korean women.

IL-34 is associated with obesity, chronic inflammation, and insulin resistance.

OBJECTIVES IL-34 is a recently identified alternative ligand for colony-stimulating factor-1 (CSF-1) receptor. IL-34 and CSF-1 are regulators of differentiation, proliferation, and survival in mononuclear phagocytes. Here, we investigated the IL-34 serum concentration and expression in human adipose tissues and any associations with insulin resistance. METHODS We recruited 19 nondiabetic obese women, 9 type 2 diabetic women, and 27 normal-weight women. Metabolic parameters, abdominal fat distribution, serum IL-34 concentration, and IL-34 mRNA expression were measured in abdominal sc adipose tissue (SAT) and visceral adipose tissue (VAT). In addition, the expression/secretion and putative effects of IL-34 were assessed in human differentiated adipocytes. Serum IL-34 concentration was measured before and 5 to 9 months after laparoscopic Roux-en-Y gastric bypass surgery was performed on the 20 obese patients. RESULTS Regardless of diabetes status, obese patients demonstrated significantly higher serum IL-34 concentrations than controls. Serum IL-34 was significantly and positively correlated with insulin resistance-related metabolic parameters. IL-34 mRNA was significantly higher in VAT than SAT. IL-34 was expressed in adipocytes as well as nonadipocytes, and expression was significantly higher during adipogenesis. In differentiated adipocytes, the expression/secretion of IL-34 was enhanced by TNFα and IL-1β. In addition, IL-34 augmented fat accumulation and inhibited the stimulatory effects of insulin on glucose transport. Moreover, serum IL-34 was significantly decreased after Roux-en-Y gastric bypass-induced weight loss. CONCLUSION The present study demonstrates, for the first time, that IL-34 is expressed in human adipose tissues and the circulating concentration is significantly elevated in obese patients. This suggests that IL-34 is associated with insulin resistance.

Hypoadiponectinemia and insulin resistance are associated with nonalcoholic fatty liver disease

We investigated the association between nonalcoholic fatty liver disease (NAFLD) and plasma adiponectin levels and insulin resistance. We recruited study subjects among one hundred and eighty one persons who were examined abdominal ultrasound at routine screening tests. A standard interview (consumption of alcohol and medical history), physical examination (height, weight, waist circumference, and blood pressure), and biochemical study (lipid parameters, aminotransferases, fasting plasma glucose, fasting insulin, and plasma adiponectin) were performed. Subjects who consumed alcohol more than moderate, evidence of viral hepatitis, toxic hepatitis, and serious cardiac, renal, or hepatic disease were excluded. Thirty-eight NAFLD patients and 53 control subjects diagnosed by ultrasound were finally analyzed. The plasma adiponectin level was significantly correlated with HDL-cholesterol (r=0. 38, p<0.001), triglycerides (r=-0.22, p=0.04), fasting insulin (r=-0.37, p<0.01), and insulin resistance by homeostasis model of assessment-insulin resistance (HOMA-IR) (r=-0.39, p<0.01), after adjusting for age, sex, and adiposity. Multiple logistic regression analysis indicated that HOMA-IR was a significant predictor of having NAFLD (odds ratio [OR]=2.38; 95% confidence interval [CI]: 1.52-5.74), while adiponectin had a protective effect against NAFLD (OR=0.22; 95% CI: 0.09-0.55). We demonstrated that hypoadiponectinemia and insulin resistance are associated with NAFLD independent of obesity.

Single nucleotide variants in the β2-adrenergic and β3-adrenergic receptor genes explained 18.3% of adolescent obesity variation

AbstractAssociations of obesity with its candidate genes, β-adrenergic receptor genes (ADRBs), peroxisome proliferator-activated receptor-γ (PPARγ), and uncoupling proteins (UCPs) were studied in Korean adolescents. We analyzed the obesity-related phenotypes body mass index (BMI), percentage of body fat, plasma leptin and insulin levels, fasting glucose concentration, and plasma lipid profile in 329 teenagers to investigate the effects of seven single nucleotide variants 252G/A, 523C/A and 1053G/C in ADRB2; Trp64Arg in ADRB3; 161C/T in PPARγ; Ala55Val in UCP2; and 210C/T in UCP3. The 1053G/C polymorphism (P < 0.05) in the ADRB2 gene and the Trp64Arg polymorphism (P < 0.01) in the ADRB3 gene were associated with BMI after adjustment for dietary energy intake. Trp64Arg polymorphism also influenced percentage of body fat (P < 0.01) and plasma leptin level (P < 0.05). Furthermore, significant interaction effects between the 1053G/C and Trp64Arg polymorphisms were observed on BMI (P < 0.01). The polymorphisms of the ADRB2 and ADRB3 genes explained 4.3% and 10.1% of the variation on BMI, and the two loci effect, including their epistasis, explained 18.3%. We concluded that 1053G/C and Trp64Arg polymorphisms of the ADRB genes additively and interactively contributed to the variation of complex adolescent obesity.

Association between serum vaspin concentrations and visceral adipose tissue in Korean subjects.

Adipokines modulate multiple signaling pathways of insulin resistance via endocrine, paracrine, or autocrine mechanisms. Visceral adipose tissue (VAT)-derived serpin (vaspin) is a novel adipokine with potential insulin-sensitizing effects. We investigated the association between serum vaspin concentrations and abdominal adiposity. We recruited subjects (N = 150) aged 20 to 69 years who visited our hospital for regular health examinations. Abdominal VAT and subcutaneous adipose tissue areas were assessed by computed tomography. We measured serum vaspin concentrations by enzyme-linked immunosorbent assay. Statistical analysis was performed after stratification, using a homeostasis model for insulin resistance (HOMA-IR). Serum vaspin concentrations correlated positively with age (r = 0.196) when data from all subjects were analyzed. In the higher-HOMA-IR group, serum vaspin levels correlated more prominently with age (r = .344) and VAT area (r = .327) although these associations were not found in the lower-HOMA-IR group. In multivariate linear regression analysis, the VAT area was independently correlated with serum vaspin concentrations in the higher-HOMA-IR group. The association between serum vaspin concentrations and VAT differs according to insulin resistance. Insulin resistance might influence the correlation between serum vaspin concentration and VAT in human subjects.