The association of lecithin retinol acyltransferase and the 25(OH)D receptor with pediatric overweight and obesity

Decreased vitamin D bio-availability with altered DNA methylation of its metabolism genes in association with the metabolic disorders among the school-aged children with degree I, II, and III obesity

Obesity is strongly associated with disturbances of vitamin D (VD) metabolites in the animal models. However, the related epidemiological evidence is still controversial, especially the different degrees of obesity children. Hence, in this present representative case-control study, 106 obesity school-age children aged 7-12 years were included and divided into different subgroups as degree I (the age- and sex-specific BMI≥95th percentile, n=45), II (BMI ≥120% percentile, n=34) and III (BMI ≥140% percentile, n=27) obesity groups across the ranges of body mass index (BMI). While the age- and sex-matched subjects without obesity were as the control group. Notably, it was significantly different of body composition, anthropological and clinical characteristics among the above four subgroups with the dose-response relationships (P<.05). Moreover, comparing with the control group, the serum VD concentrations were higher, VD metabolites like 25(OH)D, 25(OH)D3 and 1,25(OH)2D, and related hydroxylases as CYP27A1, CYP2R1 and CYP27B1 were lower in the degree I, II, and III obesity subgroups (P<.05), which were more disorder with the anthropological and clinical characteristics as the obesity was worsen in a BMI-independent manner (P<.05). However, there was a significant increase of CYP27B1 in the degree III obesity group than those in the degree I and II obesity subgroups. Furthermore, the methylation patterns on the genome-wide (Methylation/Hydroxymethylation) and VD metabolism genes (CYP27A1, CYP2R1 and CYP27B1) were negatively correlated with the worse obesity and their related expressions (P<.05). In summary, these results indicated that obesity could affect the homeostasis of VD metabolism related genes such as CYP27A1, CYP2R1, CYP27B1 and etc through abnormal DNA methylation, resulting in the disorders of VD related metabolites to decrease VD bio-availability with the BMI-independent manner. In turn, the lower levels of VD metabolites would affect the liver function to exacerbate the progression of obesity, as the Degree II and III obesity subgroups.

Abdominal obesity-related lipid metabolites may mediate the association between obesity and glucose dysregulation

BACKGROUND

Children with obesity is associated with a higher risk of cardiovascular disease (CV) risk in adulthood. This study is to explore the obesity-related lipid metabolites and identify the associations of lipid metabolites with selected CV risk in children and adolescents.

METHODS

A case-control study was designed to include a total of 197 children (aged 9-13 years, male 56.34%, 99 children in the obesity group). The lipidomics profiling was measured by ultra-high-performance liquid tandem chromatography quadrupole time-of-flight mass spectrometry.

RESULTS

Four FDR-significant abdominal obesity-related lipid metabolites were identified. Compared to the lean group, decreased phosphatidylcholine O-21:2 level (q = 0.010) and sphingomyelins d21:1 (q = 0.029) were found and two lipid metabolites levels were higher in the obese group, including phosphatidylglycerol 43:6 and one did not match with any candidate compounds in databases. After adjusting for covariates, PC3 (O-21:2) and SM (d21:1) were significantly associated with blood glucose. Mediation analysis showed that all three lipid metabolites may mediate the association between abdominal obesity and glucose regulation.

CONCLUSIONS

This study identified several novel central obesity-related lipid metabolites, and we found that PC3 (O-21:2) and SM (d21:1) were significantly associated with blood glucose, and all these lipid metabolites can mediate the association between abdominal obesity and glucose dysregulation.

IMPACT

Serum lipidomic profiles in children with abdominal obesity and their associations with selected CV risk factors were examined. Our study identified 4 lipid metabolites associated with abdominal obesity, including PC3 (O-21:2), SM (d21:1), PG (43:6), and one did not match with any candidate compounds in the databases. PC3 (O-21:2) and SM (d21:1) were significantly associated with blood glucose. Mediation analysis showed that all three lipid metabolites [PC3 (O-21:2), SM (d21:1), PG (43:6)] may mediate the association between abdominal obesity and abnormal glucose regulation. This study identified several novel obesity-related lipid metabolites.

Association of decreases in PM2.5 levels due to the implementation of environmental protection policies with the incidence of obesity in adolescents: A prospective cohort study

AIMS

To explore the association between decreased levels of particulate matter (≤2.5 µm; PM_2.5) due to the implementation of environmental protection policies and the incidence of obesity in adolescents in Chongqing, China through a prospective cohort study.

METHODS

A total of 2105 children (52.02% male; aged 7.33 ± 0.60 years at baseline) were enrolled from the Chongqing Children's Health Cohort. A mixed linear regression model was used to analyse the relationships of PM_2.5 levels with obesity indicators after adjusting for covariates. Additionally, a Poisson regression model was used to determine the relationship between PM_2.5 exposure and the incidence of overweight/obesity.

RESULTS

The average PM_2.5 exposure levels from participant conception to 2014, from 2015 to 2017, and from 2018 to 2019 were 66.64 ± 5.33 μg/m³, 55.49 ± 3.78 μg/m³, and 42.50 ± 1.87 μg/m³, respectively; these levels significantly decreased over time (P < 0.001). Throughout the entire follow-up period, the incidence of overweight/obesity after a ≥ 25 μg/m³ decrease in the PM_2.5 level was 4.57% among females; this incidence was the lowest among females who experienced remarkable decreases in PM_2.5 exposure. A 1-µg/m³ decrease in the PM_2.5 level significantly decreased the body mass index (BMI), BMI z score (BMI_z), and weight of adolescents (all P < 0.001). Compared with a < 20-μg/m³ decrease in the PM_2.5 level, a ≥ 25-μg/m³ decrease protected against increased BMI (net difference= -0.93; 95% confidence interval [CI]: (-1.23,-0.63) kg/m²), BMI_z (-0.28 (-0.39, -0.17)), weight (-1.59 (-2.44, -0.74) kg), and incidence of overweight/obesity (0.48 (0.37, 0.62), P < 0.001). Moreover, compared with a < 20-μg/m³ decrease in the PM_2.5 level, a ≥ 25-μg/m³ decrease resulted in significant absolute differences in BMI (-1.26 (-1.56, -0.96) kg/m²), BMI_z (-0.53 (-0.65, -0.40)) and weight (-3.01 (-3.8, -2.19) kg) (all P < 0.001).

CONCLUSIONS

This study showed the etiological relevance of declining PM_2.5 concentrations for the incidence of obesity in children and adolescents, suggesting that controlling ambient air pollutants may prevent the development of obesity in this age group. Continuous implementation of environmental protection policies in China has led to substantial health benefits.

The relationship of remnant cholesterol and abdominal obesity in children: A cross-sectional study

Background

Previous studies found that remnant cholesterol (RC) is a risk factor for cardiovascular diseases and childhood obesity is associated with cardiometabolic diseases. This study aimed to explore the relationship between RC and abdominal obesity in children.

Methods

A total of 5,959 children, aged 6−12 years old, were selected from a cross-sectional study in urban-rural areas of Chongqing, China. RC was calculated by total cholesterol (TC)—high-density lipoprotein (HDL-C) cholesterol—low-density lipoprotein (LDL-C) cholesterol and was divided into four groups by quartiles (Q1–Q4).

Results

Compared to children with the lowest RC (Q1), children with higher RC had significantly higher odds of abdominal obesity (Q2: OR = 1.450, 95% CI: 1.131−1.859, p < 0.05; Q3: OR = 2.127, 95% CI: 1.632−2.772, p < 0.001; Q4: OR = 2.386, 95% CI: 1.819−3.130, p < 0.001). In the stratified analyses by urban-rural areas, the odds ratios were greater in rural areas (Q2: OR = 2.228, 95% CI: 1.572−3.160, p < 0.001; Q3: OR = 3.668, 95% CI: 2.191−6.140, p < 0.001; Q4: OR = 6.490, 95% CI: 2.271−18.551, p < 0.001) than in urban areas (Q2: OR = 1.644, 95% CI: 1.192−2.266, p < 0.05; Q3: OR = 2.266, 95% CI: 1.667−3.082, p < 0.001; Q4: OR = 2.711, 95% CI: 2.005−3.665, p < 0.001).

Conclusions

Our study found that RC was positively correlated with abdominal obesity in children, and this association was higher for children living in rural areas.

Combining multiaspect factors to predict the risk of childhood hypertension incidence

Childhood hypertension has become a global public health issue due to its increasing prevalence and association with cerebral‐cardiovascular disease in adults. In this study, we developed a predictive model for childhood hypertension based on environmental and genetic factors to identify at‐risk individuals. Eighty children diagnosed with childhood hypertension and 84 children in the control group matched by sex and age from an established cohort were included in a nested case–control study. We constructed a multiple logistic regression model to analyze the factors associated with hypertension and applied the 10‐fold cross‐validation method to verify the prediction stability of the model. Childhood hypertension was found positively correlated with triglyceride level ≥150 mg/dL; low‐density lipoprotein cholesterol level ≥110 mg/dL; body mass index Z score; waist‐to‐height ratio Z score; and red blood cell count (all P < .01) and negatively correlated with the relative expression level of retinol acyltransferase; relative expression level of vitamin D receptor; and dietary intake of fiber, vitamin C and copper (all P < .05) in this study. BMI Z score, triglyceride ≥150 mg/dL, RBC count, VDR/β‐actin and LRAT/β‐actin ratios were used to construct the predictive model. The area under the receiver operating characteristic curve was 94.45% (95% CI = 89.35%∼98.65%, P < .001). The accuracy, sensitivity, specificity, positive predictive value, and negative predictive value were all above 80% in both the training and validation sets. In conclusion, this model can predict the risk of childhood hypertension and could provide a theoretical basis for early prevention and intervention to improve the cardiovascular health of children.

[Levels of fat-soluble vitamins A, D, and E and their influencing factors in children with obesity]

OBJECTIVES

To investigate the levels of fat-soluble vitamins A, D, and E in children with obesity and their influencing factors.

METHODS

A total of 273 children with obesity who attended the Department of Clinical Nutrition, Xi'an Children's Hospital, from January 2019 to April 2021 were enrolled as the obesity group. A total of 226 children with normal body weight who underwent physical examination during the same period were enrolled as the control group. Anthropometric parameters and body composition were measured for both groups, and the serum concentrations of vitamins A, D, and E were also measured.

RESULTS

Compared with the control group, the obesity group had significantly higher serum levels of vitamin A [(1.32±0.21) μmol/L vs (1.16±0.21) μmol/L, P<0.001] and vitamin E [(9.3±1.4) mg/L vs (8.3±1.2) mg/L, P<0.001] and a significant reduction in the level of 25-hydroxyvitamin D [(49±22) nmol/L vs (62±24) nmol/L, P<0.001]. In the obesity group, the prevalence rates of marginal vitamin A deficiency, vitamin D deficiency/insufficiency, and vitamin E insufficiency were 5.5% (15/273), 56.8% (155/273), and 4.0% (11/273), respectively. After adjustment for body mass index Z-score and waist-to-height ratio, serum vitamin A level was positively correlated with age (P<0.001), while vitamins E and 25-hydroxyvitamin D levels were negatively correlated with age in children with obesity (P<0.001). After adjustment for age, the serum levels of vitamin A, vitamin E and 25-hydroxyvitamin D were not correlated with degree of obesity, percentage of body fat, and duration of obesity in children with obesity, while the serum levels of vitamins A and E were positively correlated with waist-to-height ratio (P<0.001).

CONCLUSIONS

There are higher serum levels of vitamins A and E in children with obesity, especially in those with abdominal obesity, while serum vitamin D nutritional status is poor and worsens with age. Therefore, vitamin D nutritional status should be taken seriously for children with obesity, and vitamin D supplementation should be performed when necessary.

The Impact of PM2.5 on the Growth Curves of Children's Obesity Indexes: A Prospective Cohort Study

Aims

To explore the effect of long-term exposure to particulate matter with an aerodynamic diameter of 2.5 μm or less (PM2.5) on childhood obesity based on a cohort study in Chongqing.

Methods

A total of 4,284 children aged 6-8 years at baseline were enrolled from the Chongqing Children Health Cohort in 2014-2015 and were followed up in 2019. A stratified cluster sampling was applied to select the participants. A Mixed-effects linear regression model was used to examine the effect of long-term exposure to PM2.5 on the growth curve of obesity indicators [including body mass index (BMI), BMI Z-score (BMIz), and waist-to-height ratio (WHtR)]. A mixed-effects logistic regression model was used to study the dose relationship between PM2.5 exposure and the risk of obesity indicators.

Results

A higher level of accumulating exposure to PM2.5 was associated with an increased childhood obesity index, and the effect was the most significant for WHtR than BMI and BMIz. This effect was more pronounced in boys than in girls except for WHtR, and it was the most significant under the PM2.5 exposure period from pregnancy to 6 years old. Compared the annual average PM2.5 exposure level of <60 μg/m³, the WHtR and BMI were increased by 0.019 [(95% CIs): 0.014, 0.024] and 0.326 [(95% CIs): 0.037, 0.616] Kg/m² for participants living with the PM2.5 exposure level of 70-75 μg/m³, respectively. For every 5 μg/m³ increase in PM2.5 levels (from pregnancy to 6 years old), the risk of central obesity was increased by 1.26 {odds ratio [OR] (95% CIs): 1.26 (1.16, 1.37), p < 0.001} times.

Conclusions

This study confirmed a dose-response relationship between PM2.5 exposure and childhood obesity, especially central obesity, suggesting that controlling ambient air pollution can prevent the occurrence of obesity in children and adolescents.

Serum levels of vitamin D, retinol, zinc, and CRP in relation to obesity among children and adolescents

Background

The aim of this study was to examine the possible association between serum micronutrients (vitamin D, retinol, zinc), C-reactive protein (CRP), and obesity among children and adolescents.

Methods

Weight and height were measured and serum 25-hydroxy vitamin D, serum retinol, serum zinc, and CRP were measured in 2818 children and adolescents (6–17 years of age), and the data of 10 investigation sites in Zhejiang Province were used. The difference of micronutrients (vitamin D, retinol, zinc) and CRP among different nutritional status were explored by ANOVA and Chi-square test. The associated factors of micronutrients and CRP of overweight and obesity were explored by multifactor analysis.

Results

There were significant differences between male students and female students on BMI, 25(OH)D3, and CRP, and there were significant differences between children and adolescents and between students living in urban area and rural area on BMI, 25(OH)D3, retinol, and zinc(t > 1.96, p < 0.05). There were significant differences on 25(OH)D3 and CRP level among children and adolescents with different nutritional conditions (F = 2.612, 15.022, p < 0.05). In multifactor analysis, we found that female [odds ratio (OR) = 0.68, 95% CI 0.49–0.81], living in rural area (OR = 0.68, 95% CI 0.56–0.82), age (OR = 0.95, 95% CI 0.92–0.98), high CRP concentration (OR = 1.08, 95% CI 1.04–1.12) and appropriate retinol level (OR = 1.32, 95% CI 1.09–1.59) were associated with obesity compared to low/normal BMI.

Conclusion

Gender, living area, age, CRP concentration, and vitamin A status were associated with children and adolescents with overweight and obesity compared to low/normal BMI. More attention in the intervention of overweight and obesity should be paid to boys living in urban areas, and high serum concentration of CRP should also be concerned.

The Determinants of Adolescent Glycolipid Metabolism Disorder: A Cohort Study

BACKGROUND

The increased prevalence of glycolipid metabolism disorders (GLMD) in childhood and adolescents has a well-established association with adult type 2 diabetes and cardiovascular diseases; therefore, determinants of GLMD need to be evaluated during this period.

OBJECTIVES

To explore the prevalence of and risk factors for GLMD from the prenatal period through childhood and adolescence.

METHODS

A bidirectional cohort study which was established in 2014 and followed between March 1 and July 20, 2019, was used to illustrate the impact factors for GLMD. Stratified cluster sampling in urban-rural areas was used to include subjects from four communities in Chongqing. 2808 healthy children aged between 6 and 9 years in 2014 entered the cohort in 2014 and followed in 2019 with a follow-up rate of 70%. 2,136 samples (aged 11.68 ± 0.60 years) were included.

RESULTS

The prevalence rates of insulin resistance (IR), prediabetes/diabetes, and dyslipidemia were 21.02%, 7.19%, and 21.61%, respectively. Subjects with an urban residence, no pubertal development, dyslipidemia in 2014, higher family income, and higher parental education had significantly elevated fasting insulin (FI) or homeostasis model assessment of insulin resistance (HOMA-IR) levels; subjects with female sex, no pubertal development, dyslipidemia in 2014, obesity, gestational hypertension, maternal weight gain above Institute of Medicine guidelines, and single parents had increased triglyceride or triglyceride/high-density lipoprotein (HDL). Adolescents with rural residence had higher HbA1c level.

CONCLUSION

We observed that the prevalence of GLMD was high in childhood and adolescents, and rural-urban areas, sex, pubertal development, dyslipidemia in a younger age, maternal obesity, and hypertension were associated with increased GLMD risk, suggesting that implementing the community-family intervention to improve the GLMD of children is essential.

The impact of PM2.5 on children's blood pressure growth curves: A prospective cohort study

OBJECTIVE

The aim of this study was to explore the association between exposure to particulate matter with an aerodynamic diameter of 2.5 mm or less (PM2.5) and blood pressure (BP) levels in children and adolescents and to illustrate the impact of PM2.5 levels on BP growth curves in a cohort study.

METHODS

A longitudinal study was designed and included 4303 children (7617 BP measurements) living in the selected areas, and evaluations were conducted in 2014-2015 (visit 1) and followed up in 2019 (visit 2). Two-stage stratified cluster sampling was used to include urban-rural areas. A mixed linear regression model and mixed logistic regression model were used to analyze the effect of PM2.5 exposure on BP and the incidence of prehypertension and hypertension in children.

RESULTS

After adjusting for covariates, systolic blood pressure (SBP) (2.21 (95% CIs: 0. 81, 3.62), mmHg), diastolic blood pressure (DBP) (1.92 (95% CIs: 0.74, 3.11), mmHg), mean arterial pressure (MAP) (2.03 (95% CIs: 0.89, 3.17), mmHg) and heart rate (HR) (2.24 (95% CIs: 0.11, 4.37), beats/min) increased significantly in the fourth quartile of PM2.5 exposure levels compared with the first quartile (all P < 0.01). In addition, long-term exposure to PM2.5 was significantly positively correlated with SBP, DBP and MAP, and the effect was more notable in urban areas than that in rural areas. Moreover, the risk of prehypertension and hypertension incidence increased by 1.17 (95% CIs: 1.03, 1.33) fold with a one-quartile increase in PM2.5 exposure. The long-term effects of annual mean PM2.5 exposure on SBP, DBP and MAP were significant from pregnancy to 7, 3 and 4 years of age, respectively.

CONCLUSION

Long-term exposure to PM2.5 was positively associated with growth curves of hemodynamics indexed from pregnancy to childhood and adolescence, and the effect was more significant in urban areas than in rural areas.

The relationship between socioeconomic status and childhood overweight/obesity is linked through paternal obesity and dietary intake: a cross-sectional study in Chongqing, China

Background

The prevalence of obesity and overweight in childhood has increased dramatically over the past decades globally. Thus, the risk factors of overweight and obesity in children and adolescents must be studied.

Objectives

This study aimed to reveal the prevalence of childhood obesity and examine the relationship between socioeconomic status (SES) and z-body mass index (z-BMI) via parental obesity and dietary intake using path analysis.

Methods

Stratified cluster sampling was used to select 17,007 participants aged 6–12 years on two avenues per region in urban, suburban, and rural areas. Path analysis was conducted to examine the mediators between SES and z-BMI.

Results

The prevalence rates of overweight and obesity were 13.36% and 8.60%, respectively, and were positively correlated with the father’s education level, family income, a birth weight > 3000g, a parental obesity history, vegetable intake and red meat intake (all P < 0.05). Four mediators (paternal obesity history, red meat intake, vegetable intake, and nutritional supplements) were observed, and the four path analyses were significant (all P < 0.05). The adjusted total effects on z-BMI were significant for income (βTot = 0.03; P < 0.01), father’s education (βTot = 0.05; P < 0.001), and region (βTot = 0.11; P<0.001), and the total mediation effects were 20.69%, 16.67%, and 5.36%, respectively. All the variables accounted for 12.60% of the z-BMI variance.

Conclusions

The prevalence of overweight/obesity in children was notable, and the relationship between SES and z-BMI was mediated by paternal obesity history and dietary intake.

The relationship between socioeconomic status and childhood overweight/obesity is linked through paternal obesity and dietary intake: a cross-sectional study in Chongqing, China

BACKGROUND

The prevalence of obesity and overweight in childhood has increased dramatically over the past decades globally. Thus, the risk factors of overweight and obesity in children and adolescents must be studied.

OBJECTIVES

This study aimed to reveal the prevalence of childhood obesity and examine the relationship between socioeconomic status (SES) and z-body mass index (z-BMI) via parental obesity and dietary intake using path analysis.

METHODS

Stratified cluster sampling was used to select 17,007 participants aged 6-12 years on two avenues per region in urban, suburban, and rural areas. Path analysis was conducted to examine the mediators between SES and z-BMI.

RESULTS

The prevalence rates of overweight and obesity were 13.36% and 8.60%, respectively, and were positively correlated with the father's education level, family income, a birth weight > 3000g, a parental obesity history, vegetable intake and red meat intake (all P < 0.05). Four mediators (paternal obesity history, red meat intake, vegetable intake, and nutritional supplements) were observed, and the four path analyses were significant (all P < 0.05). The adjusted total effects on z-BMI were significant for income (β_Tot = 0.03; P < 0.01), father's education (β_Tot = 0.05; P < 0.001), and region (β_Tot = 0.11; P<0.001), and the total mediation effects were 20.69%, 16.67%, and 5.36%, respectively. All the variables accounted for 12.60% of the z-BMI variance.

CONCLUSIONS

The prevalence of overweight/obesity in children was notable, and the relationship between SES and z-BMI was mediated by paternal obesity history and dietary intake.

Prevalence and Risk Factors of Childhood Hypertension in Urban-Rural Areas of China: A Cross-Sectional Study

OBJECTIVE

The increased blood pressure level in children and adolescents is recognized as an essential predictor of adulthood cardiovascular disease. This study aimed to ascertain the prevalence and the urban-rural disparity of childhood hypertension in the southwest of China.

METHODS

Using stratified cluster sampling in urban and rural areas, a total of 13597 primary school children aged 6∼12 years living in the Southwest of China were included. The prevalence of hypertension was analyzed. The risk factors were collected by questionnaires, and the risk factors of childhood hypertension were analyzed by the logistic regression model.

RESULTS

The prevalence of hypertension was 13.75%, 9.02%, and 17.47% in total, urban, and rural children, respectively, and the urban-rural difference was 8.44% (95%CI: 7.32%, 9.56%). Children with obesity, maternal gestational hypertension, >10 months of breastfeeding, or low family income had a significantly increased prevalence of hypertension (29.4%, 20.00%, 16.31%, and 16.25%, respectively). Rural residence, intake of more pickle (in rural), maternal gestational hypertension (in urban), low birth weight (in rural), obesity, increased heart rate, and red blood cell counts were the risk factors of childhood hypertension. The adjusted R ² values were 13.61%, 23.25%, 10.88%, 11.12%, 12.23%, and 25.04% in the full models excluding and including serum indexes for total, urban, and rural children, respectively.

CONCLUSIONS

The prevalence of childhood hypertension is significant in the Southwest of China and alarming in rural areas, which requires community intervention. Children living in rural areas combined with obesity, low social economic status, dietary imbalance, and abnormal lipid metabolism were associated with an increased risk of hypertension, and routine care programs should be conducted to prevent childhood hypertension.