Jung Su Chang

Serum ferritin and risk of the metabolic syndrome: A population-based study

Ferritin concentrations in circulation reflect iron stores in healthy individuals. However, elevated serum ferritin (SF) concentrations have recently been implicated in the pathogenesis of the metabolic syndrome (MetS). We aim to investigate factors associated with elevated SF and to evaluate the association between SF and risk of MetS in Taiwanese adults. Data was collected from 2654 healthy individuals aged >=19 years old, who participated in the Nutrition and Health Survey in Taiwan (NAHSIT Adults 2005-2008). Mean concentrations of SF were 173±282 ng/mL (men 229±349 ng/mL and women 119±180 ng/mL). Prevalence proportion of MetS was 34.6% (men 43.1% and women 26.5%). Prevalence proportion of iron overload was 18.6% (men 21.5% and women 15.8%) and iron deficiency anemia was 5.2% (2.0% for men and 8.3% for women). Individuals with the highest SF tertile (T3) were more likely to consume higher amount of animal protein (p=0.001), betel nuts (p=0.004), and lower amounts of carbohydrates (p<0.0001), compared with the lowest SF group (T1). After adjustments, individuals with the highest SF tertile were associated with risk of MetS compared with those with the lowest (OR=1.724, 95% CI: 1.21-2.45). Serum ferritin concentrations showed a gradient relationship with individual components of MetS (all p<0.0001). Individuals with the highest SF tertile were significantly associated with fasting serum glucose (OR=2.16, 95% CI: 1.75-2.65) and serum triglyceride (OR=2.58, 95% CI: 1.07-3.22) than those with the lowest. In conclusions, our results highlight the crucial role of serum ferritin in the pathogenesis of the MetS in healthy Taiwanese adults.

Interleukin-10 as a potential regulator of hepcidin homeostasis in overweight and obese children: A cross-sectional study in Taiwan

OBJECTIVE A sharp increase in the prevalence of obesity and a decline in iron deficiency in children was observed between the two consecutive Nutrition and Health Surveys in Taiwan. The aim of this study was to evaluate the distribution of hepcidin in relation to nutritional status in children. METHODS 648 children ages 7 to 13 y living in Taipei and New Taipei City were enrolled in this study. Parameters for obesity, iron status, and inflammatory markers were evaluated. RESULTS There were no differences in the prevalence of iron deficiency and iron depletion between normal and overweight/obese children. A V-sharp hepcidin distribution curve was seen in normal weight children and overweight/obese boys. Serum hepcidin levels remained stable in overweight/obese girls during transition from childhood to teenager. Overweight/obese children had increased serum nitric oxide (NO) and interleukin (IL)-1β but decreased IL-10 concentration compared with normal weight children. A strong inverse relationship was found between IL-10 and body mass index (BMI; odds ratio (OR), 0.86, 95% confidence interval [CI], 0.83-0.89). By contrast, positive correlations were observed between BMI and IL-1β (OR, 1.60; 95% CI, 1.29-1.98); and between BMI and NO (OR, 1.04, 95% CI, 1.02-1.07). Multivariate linear regression analysis showed serum hepcidin was significantly correlated with IL-10 (β = 0.26, P < 0.0001). CONCLUSIONS Our results raise the possibility that IL-10 may play a role in iron homeostasis. Decreased circulating IL-10 concentration may temporary protect young overweight/obese girls against the development of iron deficiency. However, long-term decrease in hepcidin concentration may increase the risk for iron overload in overweight/obese children.

Interactive Effects of Dietary Fat/Carbohydrate Ratio and Body Mass Index on Iron Deficiency Anemia among Taiwanese Women

Whether being overweight or obese is associated with increased risk of iron deficiency anemia (IDA) remains controversial. We evaluated the dietary intakes and risk for IDA in relation to body mass index (BMI). One thousand two hundred and seventy-four females aged ≥19 years, enrolled in the third Nutrition and Health Survey in Taiwan (NAHSIT) 2005–2008, were selected. Half of the women were either overweight (24.0%) or obese (25.3%). The overall prevalence of anemia, iron deficiency and IDA among adult women was 19.5%, 8.6% and 6.2%. BMI showed a protective effect on IDA: overweight (odds ratio, OR: 0.365 (0.181–0.736)) and obese (OR: 0.480 (0.259–0.891)) when compared with normal weight. Univariate analysis identified increased IDA risk for overweight/obese women who consumed higher dietary fat but lower carbohydrate (CHO) (OR: 10.119 (1.267–80.79)). No such relationship was found in IDA women with normal weight (OR: 0.375 (0.036–4.022)). Analysis of interaction(s) showed individuals within the highest BMI tertile (T3) had the lowest risk for IDA and the risk increased with increasing tertile groups of fat/CHO ratio; OR 0.381 (0.144–1.008; p = 0.051), 0.370 (0.133–1.026; p = 0.056) and 0.748 (0.314–1.783; p = 0.513); for T1, T2 and T3, respectively. In conclusion, a protective effect of BMI on IDA may be attenuated in women who had increased fat/CHO ratio.

Serum ferritin contributes to racial or geographic disparities in metabolic syndrome in Taiwan

OBJECTIVES Asians and Pacific Islanders have higher circulating serum ferritin (SF) compared with Caucasians but the clinical significance of this is unclear. There is a higher prevalence of metabolic syndrome (MetS) in Taiwanese Indigenous than Han Chinese. Genetically, Indigenous are related to Austronesians and account for 2 % of Taiwans population. We tested the hypothesis that accumulation of Fe in the body contributes to the ethnic/racial disparities in MetS in Taiwan. DESIGN A population-based, cross-sectional study. SETTING National Nutrition and Health Survey in Taiwan and Penghu Island. SUBJECTS A total of 2638 healthy adults aged ≥19 years. Three ethnic groups were included. RESULTS Han Chinese and Indigenous people had comparable levels of SF. Austronesia origin was independently associated with MetS (OR = 2·61, 95 % CI 2·02, 3·36). After multiple adjustments, the odds for MetS (OR = 2·49, 95 % CI 1·15, 5·28) was significantly higher among Indigenous people in the highest SF tertile compared with those in the lowest tertile. Hakka and Penghu Islanders yielded the lowest risks (OR = 1·08, 95 % CI 0·44, 2·65 and OR = 1·21, 95 % CI 0·52, 2·78, respectively). Indigenous people in the highest SF tertile had increased risk for abnormal levels of fasting glucose (OR = 2·34, 95 % CI 1·27, 4·29), TAG (OR = 1·94, 95 % CI 1·11, 3·39) and HDL-cholesterol (OR = 2·10, 95 % CI 1·18, 3·73) than those in the lowest SF tertile. CONCLUSIONS Our results raise the possibility that ethnic/racial differences in body Fe store susceptibility may contribute to racial and geographic disparities in MetS.

Relationship between hemoglobin levels and risk for suspected non-alcoholic fatty liver in taiwanese adults

Body iron levels have recently been shown to be a strong predictor for non-alcoholic fatty liver disease (NAFLD). The aims of this study were to investigate the prevalence of NAFLD in a general adult population, and to investigate the relationship between body iron levels, NAFLD and the metabolic syndrome (MetS). 2186 adults participated in the third National Nutrition and Health Survey in Taiwan (NAHSIT, 2005-2008). The participants underwent anthropometry measurements and phlebotomy after an overnight fast, and those with excessive alcohol intake, iron overload of serum ferritin > 600 ng/ml, hepatitis viral infection and hepatocellular carcinoma were excluded. Suspected NAFLD was diagnosed by three alanine transaminase (ALT) cut-points: cut-point 1: serum ALT > 40 U/l; cut-point 2: ALT ≥ 25 U/l for male and ALT ≥ 17 U/l for female; and cut-point 3: ALT ≥ 35 U/l for male and ALT ≥ 26 U/l for female. The prevalence proportion of suspected NAFLD among Taiwanese adults was 6.6% (cut-point 1), 36% (cut-point 2); and 14.3% (cut-point 3). Body iron levels were significantly higher in individuals with suspected NAFLD compared with those without. Distribution of hemoglobin levels, but not serum ferritin levels, by decade of age showed strong correlation with the prevalence of suspected NAFLD in individuals with MetS. Multivariate adjusted odds ratio (OR) showed that the best predictors for suspected NAFLD with the MetS were hemoglobin [OR 1.43 (1.21-1.68); P < 0.0001] and hyperlipidemia [OR 1.52 (1.19-1.94); P = 0.0007]. In individuals without MetS, the adjusted OR of suspected NAFLD was markedly higher for hemoglobin [OR 1.25 (1.12-1.41); P < 0.0001]. In conclusion, adults with high hemoglobin levels (14.4 μg/dl for male and 13.2 μg/dl for female) are at the greatest risk for developing abnormal liver function. Hemoglobin test should be considered as a part of clinical evaluation for patients with NAFLD.

Serum Iron:Ferritin Ratio Predicts Healthy Body Composition and Reduced Risk of Severe Fatty Liver in Young Adult Women

Dysregulated iron metabolism is associated with altered body composition and nonalcoholic fatty liver disease (NAFLD); however, mechanisms underlying this association remain undefined. We investigated this association in 117 women. Middle-aged women (≥45 years old (y)) were heavier and had lower serum iron, higher serum hepcidin, ferritin, and severe NAFLD incidence than young adult women (<45 y). Age-adjusted linear regression analysis revealed that young adult women with the highest serum iron:ferritin ratio (Tertile 3) had a 5.08-unit increased percentage of muscle mass [β = 5.08 (1.48–8.68), p < 0.001] and a 1.21-unit decreased percentage visceral fat mass [β = −1.21 (−2.03 to −0.39), p < 0.001] compared with those with the lowest serum iron:ferritin ratio (Tertile 1; reference). The iron:ferritin dietary pattern, characterized by high consumption of beef, lamb, dairy products, fruits, and whole grains, and low consumption of refined carbohydrates (rice, noodles, and bread and pastries), and deep- and stir-fried foods, predicted a 90% [odds ratio: 0.10, 95% confidence interval: 0.02–0.47, p < 0.001] reduced risk of mild vs. moderate and severe NAFLD in young adult women. Our findings suggest that the serum iron:ferritin ratio more accurately predicts body composition and reduced risk of severe fatty liver progression in young adult women compared to middle-aged women.

Effects of melatonin on glucose homeostasis, antioxidant ability, and adipokine secretion in ICR mice with NA/STZ-induced hyperglycemia

Diabetes is often associated with decreased melatonin level. The aim was to investigate the effects of different dosage of melatonin on glucose hemostasis, antioxidant ability and adipokines secretion in diabetic institute for cancer research (ICR) mice. Forty animals were randomly divided into five groups including control (C), diabetic (D), low-dosage (L), medium-dosage (M), and high-dosage (H) groups. Groups L, M, and H, respectively, received oral melatonin at 10, 20, and 50 mg/kg of BW (body weight) daily after inducing hyperglycemia by nicotinamide (NA)/ streptozotocin (STZ). After the six-week intervention, results showed that melatonin administration increased insulin level and performed lower area under the curve (AUC) in H group (p < 0.05). Melatonin could lower hepatic Malondialdehyde (MDA) level in all melatonin-treated groups and increase superoxide dismutase activity in H group (p < 0.05). Melatonin-treated groups revealed significant higher adiponectin in L group, and lower leptin/adiponectin ratio and leptin in M and H groups (p < 0.05). Melatonin could lower cholesterol and triglyceride in liver and decrease plasma cholesterol and low-density lipoprotein-cholesterol (LDL-C) in L group, and increase plasma high-density lipoprotein-cholesterol (HDL-C) in H group (p < 0.05). Above all, melatonin could decrease oxidative stress, increase the adiponectin level and improve dyslipidemia, especially in H group. These data support melatonin possibly being a helpful aid for treating hyperglycemia-related symptoms.

High Fat Diet with a High Monounsaturated Fatty Acid and Polyunsaturated/Saturated Fatty Acid Ratio Suppresses Body Fat Accumulation and Weight Gain in Obese Hamsters

The aim of this study was to investigate the effect of a high fat diet with experimental oil consisting of 60% MUFAs (monounsaturated fatty acids) with a P/S ratio of 5 on fat deposition and lipid metabolism in obese hamsters. Hamsters were randomly assigned to a control group and a diet-induced obesity group for nine weeks. Then an additional eight-week experimental period began, during which obese hamsters were randomly divided into three groups and fed different amounts of the experimental oil mixture in their diets as follows: 5%, 15%, and 20% w/w (OB-M5, OB-M15, and OB-M20 groups, respectively). The results showed that the OB-M15 and OB-M20 groups had significantly lower blood cholesterol and higher insulin levels. Compared to the control group, the three obese groups exhibited higher hepatic fatty acid synthase activity; however, the acyl-CoA oxidase activities were also enhanced. Although dietary fat content differed, there were no differences in energy intake, final body weights, and epididymal fat weights among the four groups. These results suggest that regardless of whether the specimens had a high fat intake or not, dietary fat containing high MUFAs with a high P/S ratio had beneficial effects on maintaining blood lipid profiles and may not result in body fat accumulation in obese hamsters, possibly by promoting lipolytic enzyme activities.

Effects of different amounts and types of dietary fatty acids on the body weight, fat accumulation, and lipid metabolism in hamsters.

OBJECTIVES The aim of this study was to explore the effects of different amounts of dietary fatty acids on body weight, fat accumulation, and lipid metabolism of hamsters. METHODS Sixty male golden Syrian hamsters were randomly divided into six groups. Three of the groups (the S groups) were fed experimental diets containing 5%, 15%, and 20% (w/w) fat of soybean oil (S5, S15, and S20, respectively), and the other three groups (the M groups) were fed the same proportions of an experimental oil mixture (M5, M15, and M20, respectively). The experimental oil mixture consisted of 60% monounsaturated fatty acids (MUFAs) and a polyunsaturated-to-saturated fatty acid ratio of 5 with a mixture of soybean and canola oils. Food consumption was measured daily, and body weights were measured weekly. Serum insulin and leptin concentrations were measured and hepatic fatty acid metabolic enzymes and adipose differentiation markers were determined using an enzyme activity analysis and quantitative polymerase chain reaction. RESULTS Results showed that the weight and weight gain of the S20 group were significantly greater than those of the other five groups. When the total fat consumption increased, the body weight, weight gain, and adipose tissue weight of the S groups significantly increased, but there were no significant differences in these parameters among the M groups. Serum low-density lipoprotein cholesterol concentrations were significantly lower in the M15 and S15 groups. The S20 group had significantly higher leptin and insulin concentrations and lipoprotein lipase was promoted, but the acetyl-coenzyme A oxidase and carnitine palmitoyltransferase-1, were significantly lower. CONCLUSIONS The study demonstrated that a special experimental oil mixture (with 60% MUFAs and a ratio of 5) with high fat can prevent body weight gain and body fat accumulation by lowering insulin concentrations and increasing hepatic lipolytic enzyme activities.

Serum Ferritin Is Inversely Correlated with Testosterone in Boys and Young Male Adolescents: A Cross-Sectional Study in Taiwan

Objective The transition from childhood to teenaged years is associated with increased testosterone and a decreased iron status. It is not clear whether higher testosterone levels cause the decreased iron status, and to what extent, obesity-related inflammation influences the iron-testosterone relationship. The aim of the present study was to examine relationships of testosterone, iron status, and anti-/proinflammatory cytokines in relation to nutritional status in boys and young adolescent Taiwanese males. Methods In total, 137 boys aged 7~13 yr were included. Parameters for obesity, the iron status, testosterone, and inflammatory markers were evaluated. Results Overweight and obese (ow/obese) boys had higher mean serum testosterone, interleukin (IL)-1β, and nitric oxide (NO) levels compared to their normal-weight counterparts (all p<0.05). Mean serum ferritin was slightly higher in ow/obese boys compared to normal-weight boys, but this did not reach statistical significance. A multiple linear regression showed that serum ferritin (β = -0.7470, p = 0.003) was inversely correlated with testosterone, while serum IL-10 (β = 0.3475, p = 0.009) was positively associated with testosterone after adjusting for covariates. When normal-weight boys were separately assessed from ow/obesity boys, the association between testosterone and serum ferritin became stronger (β = -0.9628, p<0.0001), but the association between testosterone and IL-10 became non-significant (β = 0.1140, p = 0.4065) after adjusting for covariates. In ow/obese boys, only IL-10 was weakly associated with serum testosterone (β = 0.6444, p = 0.051) after adjusting for age. Conclusions Testosterone and serum ferritin are intrinsically interrelated but this relationship is weaker in ow/obese boys after adjusting for age.