Association of metabolic syndrome components with insulin resistance in normal weight population: the Qazvin Metabolic Diseases study

Optimal Threshold of Homeostasis Model Assessment of Insulin Resistance to Identify Metabolic Syndrome in a Chinese Population Aged 45 Years or Younger

BACKGROUND

Metabolic syndrome (MetS) is regarded as a major risk factor for diabetes mellitus and cardiovascular disease (CVD). The optimal threshold of the homeostasis model assessment of insulin resistance (HOMA-IR) has been established for predicting MetS in diverse populations and for different ages. This study assessed the serum HOMA-IR level in a healthy Chinese population aged ≤45 years to determine its relationship with metabolic abnormalities.

METHODS

Cross-sectional study data were collected from health checkup records of Chinese adults aged ≥18 years between 2013 and 2016 at Xiamen Chang Gung Hospital. Participants completed a standardized questionnaire, which was followed by a health examination and blood sample collection. Exclusion criteria were as follows: history of known CVDs; liver, kidney, or endocrine diseases or recent acute illness; hypertension; hyperlipidemia; and pregnancy or lactation.

RESULTS

The clinical and laboratory characteristics of 5954 men and 4185 women were analyzed. Significant differences were observed in all assessed variables (all P < 0.05). The optimal cutoff point of HOMA-IR for predicting MetS was 1.7 in men and 1.78 in women.

CONCLUSIONS

We aimed to determine the optimal cutoff point of HOMA-IR for predicting MetS in a healthy Chinese population aged ≤45 years. The findings of this study would provide an evidence-based threshold for evaluating metabolic syndromes and further implementing primary prevention programs, such as lifestyle changes in the target population.

Level of maternal triglycerides is a predictor of fetal macrosomia in non-obese pregnant women with gestational diabetes mellitus

BACKGROUND

The role of maternal serum triglycerides (TGs) in the development of fetal macrosomia in different subgroups of body mass index (BMI) has received little attention. The aim of this study was to determine the association between the level of maternal TGs and fetal macrosomia in Iranian pregnant women of different BMI subgroups with gestational diabetes mellitus (GDM).

METHODS

This cohort study was conducted on 305 pregnant women with GDM referred for glucose control to Kowsar Hospital in Qazvin, Iran. Level of TGs was measured on the 24th-28th weeks of pregnancy. The ROC curve of the level of TGs was depicted in BMI subgroups to predict fetal macrosomia. Logistic regression analysis was used to determine the risk of macrosomia per 1-SD increase in the level of TGs.

RESULTS

The prevalence of hypertriglyceridemia did not significantly differ across BMI subgroups. Macrosomia was more prevalent in obese women (32.2%) than overweight (19.1%) and normal weight (11.1%) women (P < 0.05). A 1-SD increase in the level of TG was associated with 4.2 and 1.9 times increased risk of macrosomia in normal weight (P < 0.01) and overweight (P < 0.01) women, respectively. Serum level of TGs was not associated with macrosomia in any adjustment models in obese women. The area under the curve of the level of TGs for macrosomia was 0.828 (95% CI: 0.712-0.911, P < 0.001) and 0.711 (95% CI: 0.639-0.775, P < 0.001) in normal weight and overweight women, respectively.

CONCLUSION

Hypertriglyceridemia was a predictor of macrosomia in non-obese women. More studies on different ethnicities and lifestyles are necessary to determine the association between the level of maternal TG and fetal macrosomia in BMI subgroups.

Profiling of plasma metabolites in postmenopausal women with metabolic syndrome

Objective:

The aim of the study was to investigate the associations of amino acids and other polar metabolites with metabolic syndrome (MetS) in postmenopausal women in a lean Asian population.

Methods:

The participants were 1,422 female residents enrolled in a cohort study from April to August 2012. MetS was defined according to the National Cholesterol Education Program Adult Treatment Panel III modified for Japanese women. Associations were examined between MetS and 78 metabolites assayed in fasting plasma samples using capillary electrophoresis-mass spectrometry. Replication analysis was performed to confirm the robustness of the results in a separate population created by random allocation.

Results:

Analysis was performed for 877 naturally postmenopausal women, including 594 in the original population and 283 in the replication population. The average age, body mass index, and levels of high- and low-density lipoprotein cholesterol of the entire population were 64.6 years, 23.0 kg/m², 72.1 mg/dL, and 126.1 mg/dL, respectively. There was no significant difference in low-density lipoprotein cholesterol levels between women with and without MetS. Thirteen metabolites were significantly related to MetS: multiple plasma amino acids were elevated in women with MetS, including branched-chain amino acids, alanine, glutamate, and proline; and alpha-aminoadipate, which is generated by lysine degradation, was also significantly increased.

Conclusions:

Our large-scale metabolomic profiling indicates that Japanese postmenopausal women with MetS have abnormal polar metabolites, suggesting altered catabolic pathways. These results may help to understand metabolic disturbance, including in persons with normal body mass index and relatively high levels of high-density lipoprotein cholesterol, and may have clinical utility based on further studies.

[Association of waist-to-hip ratio with insulin resistance in non-diabetic normal-weight individuals: a cross-sectional study]

OBJECTIVE

To explore the relationship between waist-to-hip ratio (WHR) and insulin resistance(IR) in non-diabetic normal-weight individuals and investigate how this association differs between male and femalesubjects.

METHODS

From June to October, 2012, we performed a cross-sectional survey among 2142 community-based non-diabetic Chinese participants, who were divided into 4 groups according to the gender-specific quartiles of WHR. Homeostatic model assessment of insulin resistance (HOMA-IR), calculated as the product of fasting plasma glucose (mmol/L) and fasting insulin (mU/L) divided by 22.5, was used as the indicator of insulin resistance. Logistic regression models were used to explore the association of WHR with IR in these subjects.

RESULTS

In the unadjusted model, WHR was significantly associated with IR in women (OR=6.60, 95%CI: 2.86-15.26, P<0.001); the association was still significant (OR=3.28, 95%CI: 1.34-8.04, P=0.009) after adjustment for the potential confounders including the history of hypertension, coronary heartdisease, current smoker, physical inactivity, and body mass index.

CONCLUSION

WHR is independently associated with IR in non-diabetic Chinese women with normal body weight.

Swimming training alleviated insulin resistance through Wnt3a/β-catenin signaling in type 2 diabetic rats

OBJECTIVES

Increasing evidence suggests that regular physical exercise improves type 2 diabetes mellitus (T2DM). However, the potential beneficial effects of swimming on insulin resistance and lipid disorder in T2DM, and its underlying mechanisms remain unclear.

MATERIALS AND METHODS

Rats were fed with high fat diet and given a low dosage of Streptozotocin (STZ) to induce T2DM model, and subsequently treated with or without swimming exercise. An 8-week swimming program (30, 60 or 120 min per day, 5 days per week) decreased body weight, fasting blood glucose and fasting insulin.

RESULTS

Swimming ameliorated lipid disorder, improved muscular atrophy and revealed a reduced glycogen deposit in skeletal muscles of diabetic rats. Furthermore, swimming also inhibited the activation of Wnt3a/β-catenin signaling pathway, decreased Wnt3a mRNA and protein level, upregulated GSK3β phosphorylation activity and reduced the expression of β-catenin phosphorylation in diabetic rats.

CONCLUSION

The trend of the result suggests that swimming exercise proved to be a potent ameliorator of insulin resistancein T2DM through the modulation of Wnt3a/β-catenin pathway and therefore, could present a promising therapeutic measure towards the treatment of diabetes and its relatives.

Association Between the Visceral Adiposity Index and Homeostatic Model Assessment of Insulin Resistance in Participants With Normal Waist Circumference

We assessed the correlation between the visceral adiposity index (VAI; a useful indicator of adipose distribution and function) and homeostatic model assessment of insulin resistance (HOMA-IR) in participants with normal waist circumference. A cross-sectional study was conducted, which included 1834 Chinese adults. The blood pressure, anthropometric measurements, fasting and postprandial blood glucose, fasting insulin, and lipid profiles were measured. The VAI and HOMA-IR were calculated. Participants were divided into 4 groups according to the HOMA-IR level, and the correlation between the VAI and HOMA-IR was analyzed. The VAI gradually increased across the HOMA-IR quartiles ( P < .05), and a Pearson correlation analysis showed that VAI was positively related to the HOMA-IR ( P < .001) in males and females. After adjusting for the other covariates, VAI was independently correlated with the HOMA-IR. A logistic regression analysis indicated that VAI elevation was the main risk factor for the increased HOMA-IR in both genders. Overall, the VAI was closely correlated with the HOMA-IR in a population without central obesity.