Adolescent Obesity and Insulin Resistance: Roles of Ectopic Fat Accumulation and Adipose Inflammation

Eicosapentaenoic and Docosahexaenoic Acids Differentially Alter Gut Microbiome and Reverse High-Fat Diet-Induced Insulin Resistance

SCOPE

To assess the individual effects of dietary eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on insulin resistance (IR), gut microbiome, and gut metabolites in high-fat-diet-induced obese (DIO) mice.

METHODS AND RESULTS

DIO mice are fed an either high-fat diet (HFD), EPA (1% w/w) enriched HFD, or DHA (1% wt/wt) enriched HFD for 15 weeks. Both EPA and DHA supplements reverse hyperglycemia and IR but do not affect body weight in DIO mice while DHA exhibits a more pronounced ameliorative effect in male mice. Both EPA- and DHA-enriched Lactobacillus and short-chain fatty acids (SCFAs)-producing species from Lachnospiraceae while reduced lipopolysaccharide (LPS)-producing Bilophila and Escherichia/Shigella. Compared with EPA, DHA-supplemented mice have more abundant propionic/butyric acid-producing bacteria, including Coprococcus, Butyricimonas synergistica, Bacteroides acidifaciens, and Intestinimonas, and less-abundant LPS-correlated species Streptococcus and p-75-a5. The shifts in gut microbiome co-occurred with the changes in levels of propionic/butyric acid, circulating LPS, and serotonin. Additionally, EPA/DHA supplementation attenuates adipose inflammation with upregulated glucose transporter 4 and Akt phosphorylation, indicating the improvement of insulin signaling.

CONCLUSION

EPA and DHA differentially reverse IR and relieve adipose inflammation while modulating gut microbiome and SCFAs/LPS production, underscoring the gut-adipose axis as a primary target of EPA/DHA.

Prevalence of prediabetes and type 2 diabetes in children with obesity and increased transaminases in European German-speaking countries. Analysis of the APV initiative

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD), prediabetes and type 2 diabetes mellitus are known to be closely linked with obesity as early as during childhood.

OBJECTIVES

The study aimed to determine the prevalence of prediabetes and T2DM in children with obesity with or without increased transaminases.

METHODS

Data from the observational multicentre (n = 51), cross-sectional Adipositas Patienten Verlaufsbeobachtung registry were analyzed. Mild increase (mild group) was defined by alanine transaminase (ALT) >24 to ≤50 U/L and moderate to severe increase (advanced group) by ALT > 50 U/L. Prediabetes and T2DM were defined according to recent IDF/ISPAD guidelines.

RESULTS

The prevalence of prediabetes and T2DM was 11.9% (95% CI: 11.0-12.8) and 1.4% (95% CI: 1.1-1.7) among all participants (n = 4932; male = 2481; mean age 12.9 ± 2.7 years; BMI-SDS 2.1 ± 0.5; Tanner stage 3.2 ± 1.5). The prevalence of impaired glucose metabolism (prediabetes and T2DM) was 13.8% (95% CI: 12.1-15.4) in the mild, 21.9% (95% CI: 18.8-25.1) in the advanced group, 10.7% (95% CI: 9.4-11.9) in the control group. Mild and advanced groups had greater odds ratios for prediabetes [1.42; 95% CI: 1.17-1.72, 2.26-fold; (1.78-2.86), respectively], the advanced group also for T2DM [2.39 (1.36-4.21)] compared to controls. While an increase in transaminases predominantly affected boys, girls within the advanced group had a higher T2DM prevalence than males (5.4 vs. male 2.1%).

CONCLUSIONS

Children with obesity and increased liver transaminases as surrogates of NAFLD should be screened for T2DM.

MRI estimated changes in visceral adipose tissue and liver fat fraction in patients with obesity during a very low-calorie-ketogenic diet compared to a standard low-calorie diet

AIM

To compare the changes in visceral adipose tissue (VAT), liver fat fraction, and liver stiffness using quantitative magnetic resonance imaging (MRI) during a very-low-calorie ketogenic (VLCK) diet and a standard low-calorie diet (LC).

MATERIALS AND METHODS

The study involved secondary analysis of prospective collected clinical data. Patients undergoing weight loss interventions were randomised to either a LC or a VLCK diet. VAT, liver fat fraction, and stiffness were measured at baseline and after 2 months.

RESULTS

Forty-six patients were included; 39 patients were evaluated at baseline and at 2 months follow-up. Mean weight loss was -9.7±3.8 kg (interquartile range [IQR]: -12.3; -7 kg) in the VLCK group and -1.67±2.2 kg (IQR: -3.3, -0.1 kg) in the LC group (p<0.0001). Mean VAT reductions were -39.3±40 cm² (IQR: -52, -10 cm²) and -12.5±38.3 cm² (IQR: -29, 5 cm²; p=0.0398), and mean liver proton density fat fraction (PDFF) reductions were -4.77±4.2% (IQR: -7.3, -1.7%) and -0.79±1.7%, (IQR: -1.8, -0.4%; p<0.005) in the VLCK group and in the LC group, respectively. No significant changes in liver stiffness occurred from baseline to follow-up.

CONCLUSION

A VLCK diet resulted in greater weight loss than a standard low-calorie diet and in significantly greater reduction in liver PDFF. As anthropometric measurements may not correlate with liver fat changes, it may be advantageous to include quantitative MRI to the monitoring strategies of patients undergoing weight-loss programmes.

Childhood obesity and the associated rise in cardiometabolic complications

Childhood obesity is one of the most serious global public-health challenges of the twenty-first century. Over the past four decades, the number of children and adolescents with obesity has risen more than tenfold. Worldwide, an increasing number of youth are facing greater exposure to obesity throughout their lives, and this increase will contribute to the early development of type 2 diabetes, fatty liver and cardiovascular complications. Herein, we provide a brief overview of trends in the global shifts in, and environmental and genetic determinants of, childhood obesity. We then discuss recent progress in the elucidation of the central role of insulin resistance, the key element linking obesity and cardiovascular-risk-factor clustering, and the potential mechanisms through which ectopic lipid accumulation leads to insulin resistance and its associated cardiometabolic complications in obese adolescents. In the absence of effective prevention and intervention programs, childhood obesity will have severe public-health consequences for decades to come.

Overfeeding During Lactation in Rats is Associated with Cardiovascular Insulin Resistance in the Short-Term

Childhood obesity is associated with metabolic and cardiovascular comorbidities. The development of these alterations may have its origin in early life stages such as the lactation period through metabolic programming. Insulin resistance is a common complication in obese patients and may be responsible for the cardiovascular alterations associated with this condition. This study analyzed the development of cardiovascular insulin resistance in a rat model of childhood overweight induced by overfeeding during the lactation period. On birth day, litters were divided into twelve (L12) or three pups per mother (L3). Overfed rats showed a lower increase in myocardial contractility in response to insulin perfusion and a reduced insulin-induced vasodilation, suggesting a state of cardiovascular insulin resistance. Vascular insulin resistance was due to decreased activation of phosphoinositide 3-kinase (PI3K)/Akt pathway, whereas cardiac insulin resistance was associated with mitogen-activated protein kinase (MAPK) hyperactivity. Early overfeeding was also associated with a proinflammatory and pro-oxidant state; endothelial dysfunction; decreased release of nitrites and nitrates; and decreased gene expression of insulin receptor (IR), glucose transporter-4 (GLUT-4), and endothelial nitric oxide synthase (eNOS) in response to insulin. In conclusion, overweight induced by lactational overnutrition in rat pups is associated with cardiovascular insulin resistance that could be related to the cardiovascular alterations associated with this condition.

Interleukin-38 increases the insulin sensitivity in children with the type 2 diabetes

The prevalence of type 2 diabetes mellitus (DM) is increasing in the children population. It is well known that inflammation contributes to the type 2 DM pathogenesis. Interleukin 38 (IL-38) is one newly identified anti-inflammatory factor. Therefore, we investigated whether the expression level of IL-38 is associated with type 2 DM in the children and the underlying mechanism. Children with recently diagnosed type 2 diabetes mellitus were recruited and studied. The healthy subjects without glucose metabolism abnormalities were used as controls. The IL-38 expression level was determined by quantitative PCR and ELISA (Enzyme-linked immunoassay). Statistic analysis showed that the IL-38 level was significantly associated with type 2 DM and insulin resistance in the children. The patients were then divided into two groups, one group sensitive to insulin therapy while the other resistant to insulin therapy. Data showed that the IL-38 was highly expressed in the group sensitive to insulin therapy. In the mice model, overexpressing the IL-38 could suppress the expression of IL-36, a pro-inflammatory factor, and also the diabetes development. Thus our results showed that higher IL-38 was associated with the increased insulin sensitive in children with type 2 DM and inhibited T2DM development in the mouse model through suppressing the function of IL-36.

Efficacy of a 2-Month Very Low-Calorie Ketogenic Diet (VLCKD) Compared to a Standard Low-Calorie Diet in Reducing Visceral and Liver Fat Accumulation in Patients With Obesity

Background: Currently the treatment of non-alcoholic fatty liver disease (NAFLD) is based on weight loss through lifestyle changes, such as exercise combined with calorie-restricted dieting. Objectives: To assess the effects of a commercially available weight loss program based on a very low-calorie ketogenic diet (VLCKD) on visceral adipose tissue (VAT) and liver fat content compared to a standard low-calorie (LC) diet. As a secondary aim, we evaluated the effect on liver stiffness measurements. Methods: Open, randomized controlled, prospective pilot study. Patients were randomized and treated either with an LC or a VLCKD and received orientation and encouragement to physical activity equally for both groups. VAT, liver fat fraction, and liver stiffness were measured at baseline and after 2 months of treatment using magnetic resonance imaging. Paired t-tests were used for comparison of continuous variables between visits and unpaired test between groups. Categorical variables were compared using the χ²-test. Pearson correlation was used to assess the association between VAT, anthropometric measures, and hepatic fat fraction. A significance level of the results was established at p < 0.05. Results: Thirty-nine patients (20 with VLCKD and 19 with LC) were evaluated at baseline and 2 months of intervention. Relative weight loss at 2 months was -9.59 ± 2.87% in the VLCKD group and -1.87 ± 2.4% in the LC group (p < 0.001). Mean reductions in VAT were -32.0 cm² for VLCKD group and -12.58 cm² for LC group (p < 0.05). Reductions in liver fat fraction were significantly more pronounced in the VLCKD group than in the LC group (4.77 vs. 0.79%; p < 0.005). Conclusion: Patients undergoing a VLCKD achieved superior weight loss, with significant VAT and liver fat fraction reductions when compared to the standard LC diet. The weight loss and rapid mobilization of liver fat demonstrated with VLCKD could serve as an effective alternative for the treatment of NAFLD. Clinical Trial Registration: ClinicalTrials.gov, identifier: NCT04322110.

Increased Energy Expenditure and Energy Loss Through Feces Contribute to the Long-Term Outcome of Roux-en-Y Gastric Bypass in a Diet-Induced Obese Mouse Model

BACKGROUND

Roux-en-Y gastric bypass (RYGB) has been proved to be more effective than other bariatric procedures in the long term on body-weight loss and remission of diabetes. However, the mechanism remains poorly understood. Long-term changes in energy metabolism after RYGB have rarely been reported.

OBJECTIVE

To investigate the long-term effects of RYGB on energy metabolism on a diet-induced obesity (DIO) mouse model.

METHODS

DIO mice fed a high-fat diet were assigned to two groups: RYGB (n=8) and sham (n=7), followed by high-fat diet feeding until 12 weeks after surgery. Body weight and food intake were recorded weekly. Measurement of body composition and energy metabolism by metabolic chamber were conducted at weeks 4, 8, and 12 after surgery. Fecal energy measurement, intraperitoneal glucose-tolerance tests, and insulin-tolerance tests were conducted at postoperative week 12.

RESULTS

Food intake was reduced in the RYGB group within the first 3 weeks after surgery and increased to the same as the sham group from postoperative week 4. At 12 weeks after surgery, body weight had reduced by 36%±3.2% in the RYGB group compared to a 16%±2% body-weight gain in the sham group, while fat mass had reduced significantly in the RYGB group compared to the sham group (9.2%±1.5% versus 30.1%±0.7%). Energy expenditure was significantly higher at postoperative week 8 in the RYGB group than the sham group. In comparison with the sham group, the respiratory exchange ratio was unchanged, decreased, and increased in the RYGB group at postoperative weeks 4, 8, and 12, respectively. Fecal energy measurement showed that feces from mice in the RYGB group contained higher energy levels than the sham group. Glucose metabolism had significantly improved in the RYGB group, in contrast to the sham group, demonstrated by intraperitoneal glucose tolerance tests (AUC 1,502±104 versus 2,277±198, respectively) and insulin tolerance tests (AUC 524±50 versus 838±63, respectively).

CONCLUSION

Increased energy expenditure and energy loss through feces contribute to long-term body-weight control after RYGB. Enhanced glucose utilization might play a role in long-term improvement in glucose metabolism.

Enhanced Myeloid Leukocytes in Obese Children and Adolescents at Risk for Metabolic Impairment

Objective: We aimed to examine if myeloid leukocyte profiles are associated with metabolic impairment in children and adolescents with obesity, and if sex, age, or race influence this relationship. Methods: 282 children ages 8-17 were evaluated. Predictor measures were absolute neutrophil counts (ANC), absolute monocyte count, monocyte subtypes and C reactive protein (CRP). Outcome variables were waist circumference, fasting glucose and insulin, HOMA-IR, HbA1c (%) and lipid profiles. Pearson correlation coefficients were used to determine associations between predictor and outcome variables. Wilcoxon two-sample tests were used to evaluate differences by sex. Results: CRP (p < 0.0001), ANC (p < 0.0018), and classical monocytes (p = 0.05) were significantly higher in children with obesity. CRP, ANC and classical monocytes showed positive correlations with waist circumference, insulin, HOMA-IR and triglycerides. CRP was positively associated with ANC overall (p = 0.05). ANC demonstrated positive correlation with monocytes (p < 0.001). The associations between predictor and outcome variables were influenced by sex, race, and age. Conclusions: CRP and myeloid leukocyte populations, specifically classical monocytes and neutrophils associate with both body composition and metabolic parameters in children with obesity suggesting that these cells may play a critical role in metabolic impairment. Race, gender and age interactions between monocytes and metabolic parameters were significant.

Muscle Insulin Resistance in Youth with Obesity and Normoglycemia is Associated with Altered Fat Metabolism

OBJECTIVE

This study aimed to phenotype and compare adipose, hepatic, and muscle insulin sensitivity (IS) in a diet- and physical activity-controlled cohort of normoglycemic youth with obesity with that of participants without obesity (controls) to distinguish early metabolic abnormalities in pediatric obesity.

METHODS

Thirty-eight participants (17 in the control group [BMI < 85th percentile] and 21 youth with obesity [BMI ≥ 95th percentile]; age: 12-21 years; 76% female; Tanner stage 4-5; sedentary) were enrolled. Tissue-specific IS was measured using a four-phase hyperinsulinemic-euglycemic clamp with glucose and glycerol isotope tracers to assess suppression of endogenous glucose release and lipolysis by insulin. Intramyocellular lipid content was assessed by 1 H-magnetic resonance spectroscopy, and hepatic fat fraction (HFF) and visceral fat were assessed by magnetic resonance imaging. Calf-muscle mitochondrial activity was measured with exercise-stimulated 31 P-magnetic resonance spectroscopy.

RESULTS

Youth with obesity had higher HFF (P < 0.001), visceral fat (P = 0.024), and intramyocellular lipid content (P = 0.017) and lower muscle (glucose clearance rate [P < 0.001]), adipose (P < 0.0001), and hepatic IS (P < 0.003). Mitochondria postexercise response was not different. In participants with obesity, muscle IS inversely correlated with HFF (r = 0.700, P = 0.002) and suppressed free fatty acid concentrations (r = -0.65, P = 0.003).

CONCLUSIONS

Inactive normoglycemic youth with obesity had decreased muscle, adipose, and hepatic IS. Free fatty acids and liver fat were inversely associated with muscle IS, which argues for lipid-targeted interventions.

Associations of Added Sugar from All Sources and Sugar-Sweetened Beverages with Regional Fat Deposition in US Adolescents: NHANES 1999-2006

BACKGROUND

The relative distribution of upper- versus lower-body fat may be an important determinant of cardiometabolic disease risk in youths. Dietary components associated with adolescent regional body fat distribution require further investigation.

OBJECTIVE

To evaluate associations of added sugar intake overall and from sugar-sweetened beverages (SSBs) with relative upper-body fat deposition in US adolescents.

METHODS

This was a cross-sectional analysis of data from 6585 adolescents (aged 12-19 y) in the NHANES cycles 1999-2006. Trunk, leg, and total fat mass were assessed by DXA. Participants were grouped into categories of total and SSB added sugar intake as a percentage of total energy intake (TEI) in 5% increments. Stepwise multivariable linear regression was used to examine associations of added sugar intake with truncal-to-leg fat ratio (TLR) and truncal-to-total fat ratio (TTR).

RESULTS

There were no associations of total added sugar intake with TLR or TTR. For SSB added sugar, compared with the lowest category of intake (<2% TEI), the highest category (>22% TEI) was associated with higher log-TLR [β (95% CI): >22% TEI versus <2% TEI: 0.05 (0.01, 0.09)] and TTR [1.30 (0.53, 2.07)] in the partially adjusted model with sex, age, race/ethnicity, income, physical activity, and smoking status as covariates (P-trend = 0.0001 for both). When BMI z-score and TEI were added as covariates, the magnitude of the associations were attenuated, but remained significant [log-TLR β (95% CI): 0.03 (0.005, 0.06), P-trend = 0.0018; TTR β (95% CI): 0.75 (0.27, 1.23), P-trend = 0.0004].

CONCLUSIONS

These findings support that added sugar from beverages is associated with higher upper-body adiposity, though the magnitude and clinical significance of the associations may be small, especially when adjusted for BMI and TEI. Additional studies are needed to elucidate the underlying biological mechanisms to explain these findings.

Childhood obesity: Aetiology, comorbidities, and treatment

Obesity is currently considered a global epidemic, and its implications in mortality and morbidity in a paediatric patient and in adulthood are increasingly important. The objective of this article is to review in detail the definition of obesity according to age group, and, in turn, the epidemiology of this entity worldwide and in South America. Available evidence about pathophysiology and, additionally, associated comorbidities are reported in some of the most important and clinically relevant body systems. The recommendations on pharmacological and nonpharmacological management through changes in lifestyle and relevant aspects of bariatric surgery in the paediatric population are also described.

2-Aminoadipic acid (2-AAA) as a potential biomarker for insulin resistance in childhood obesity

Insulin resistance is an important clinical feature of metabolic syndrome, which includes obesity and type 2 diabetes. Increased adipose energy storage in obesity promote insulin resistance and other metabolic adverse effects. To identify a new link between adipocyte and insulin resistance, we performed targeted metabolite profiling of differentiated adipocytes and studied the association between adipogenic metabolites and insulin resistance. We found a correlation between 2-aminoadipic acid (2-AAA) and adipogenic differentiation. Also, circulatory 2-AAA was positively associated with obesity-related factors (fat mass, fat percent, waist circumference, BMI, BMI z-score, triglycerides, insulin, and HOMA-IR) at baseline and after 2 years in the children cohort study. Of these factors, increased BMI z-score and HOMA-IR were the primary independent factors associated with higher 2-AAA levels, and the baseline 2-AAA level was an indicator of the BMI z-score after 2 years. To validate the relationship between 2-AAA and obesity-related factors, we analyzed changes in 2-AAA levels following obesity intervention programs in two independent studies. In both studies, changes in 2-AAA levels during the intervention period were positively correlated with changes in the BMI z-score and HOMA-IR after adjusting for confounders. Moreover, the 2-AAA levels were increased in cell and mouse models of obesity-related insulin resistance. Excess 2-AAA levels led to impaired insulin signaling in insulin-sensitive cells (liver, skeletal muscle and adipose cells) and caused abnormal gluconeogenesis. Our results demonstrate that 2-AAA is associated with adipogenesis and insulin resistance. In this regard, 2-AAA could be a potential biomarker of obesity and obesity-related metabolic disorders.

Comparisons of Visceral Adiposity Index, Body Shape Index, Body Mass Index and Waist Circumference and Their Associations with Diabetes Mellitus in Adults

The associations between visceral adiposity index (VAI), body shape index and diabetes in adults were inconsistent. We assessed the predictive capacity of VAI and body shape index for diabetes by comparing them with body mass index (BMI) and waist circumference (WC). We used the data of 5838 Chinese men and women aged ≥18 years from the 2009 China Health and Nutrition Survey. Multivariate logistic regression analysis was performed to examine the independent associations between Chinese VAI (CVAI) or body shape index and diabetes. The predictive power of the two indices was assessed using the receiver-operating characteristic (ROC) curve analysis, and compared with those of BMI and WC. Both CVAI and body shape index were positively associated with diabetes. The odds ratios for diabetes were 4.9 (2.9–8.1) and 1.8 (1.2–2.8) in men, and 14.2 (5.3–38.2) and 2.0 (1.3–3.1) in women for the highest quartile of CVAI and body shape index, respectively. The area under the ROC (AUC) and Youden index for CVAI was the highest among all four obesity indicators, whereas BMI and WC are better indicators for diabetes screening. Higher CVAI and body shape index scores are independently associated with diabetes risk. CVAI has a higher overall diabetes diagnostic ability than BMI, WC and body shape index in Chinese adults. BMI and WC, however, are more appealing as screening indicators considering their easy use.

Glycemic control and lipid outcomes in children and adolescents with type 2 diabetes

BACKGROUND

The incidence of type 2 diabetes (T2DM) in children has increased dramatically. However, limited published information is known about the glycemic control and lipid outcomes in pediatric T2DM outside of clinical trials.

OBJECTIVES

To determine the glycemic control and lipid measure outcomes at one and three- year follow-up in children with T2DM.

METHODS

A retrospective electronic medical record review of children with T2DM at the Children's Hospital of Alabama over a 12-year period.

RESULTS

There were 301 patients with a diagnosis of T2DM who had a 1-year follow-up visit, of which 184 also had a 3-year follow-up. Most patients (78%) received either insulin with metformin or insulin alone at diagnosis. At one year, 37% of the cohort achieved 'optimal glycemic control' (HbA1C ≤6.5%) and 58% of patients achieved durable glycemic control (HbA1C ≤8%). Optimal glycemic control was seen in 48 patients at 3 years. The patients treated with insulin (alone or in combination with metformin) tended to have higher HbA1C at diagnosis, but had improved lipid and glycemic outcomes at follow-up. The group treated with insulin along with metformin had significant improvements in non-HDL, HDL and TC/HDL ratios. The effects of insulin treatment on glycemic control at 3 years were not statistically significant.

CONCLUSION

With the current modality of treatment, only a minority of patients achieve optimal glycemic control at 1 and 3 years of follow-up. Studies are warranted to further elucidate the optimal therapies in the management of pediatric T2DM.

Truncal-to-leg fat ratio and cardiometabolic disease risk factors in US adolescents: NHANES 2003-2006

BACKGROUND

This study aims to describe patterns of truncal versus peripheral fat deposition measured by truncal-to-leg fat ratio (TLR) in adolescents and examine associations of TLR with cardiometabolic (CMD) risk factors.

METHODS

Data were from 3810 adolescents (12-19 years old) in the National Health and Examination Survey (NHANES) 2003-2006. Body fat was assessed by dual-energy X-ray absorptiometry, and CMD risk factors were determined by blood samples and physical examination. Linear and logistic regressions adjusted for BMI z-score and other covariates were used to examine associations of TLR with CMD risk factors as continuous and dichotomized outcomes, respectively.

RESULTS

Adolescents who were Mexican American, who have lower income, and with obesity had the highest mean TLR (all p < 0.05). In linear regression, increasing TLR was associated positively with homeostasis model assessment of insulin resistance (HOMA-IR), triglycerides, total cholesterol, systolic blood pressure (BP), c-reactive protein, and alanine aminotransferase (ALT), and negatively with high-density lipoprotein (HDL) cholesterol in both sexes (p < 0.05). TLR was also associated with diastolic BP in boys and low-density lipoprotein cholesterol in girls (p < 0.05). A similar pattern of findings resulted from logistic regression. When further stratified by race/ethnicity, TLR was positively associated with high triglycerides, total cholesterol, and ALT for White and/or Mexican American (p < 0.05), but not Black adolescents, while associations with HOMA-IR and HDL were significant for all race/ethnicities.

CONCLUSIONS

In this cohort of adolescents, TLR was associated with several risk factors independent of BMI z-score, although some findings were sex or race/ethnicity specific. Body fat distribution may be an important determinant of future CMD.

Partitioning of radiological, stress and biochemical changes in pre-diabetic women subjected to Diabetic Yoga Protocol

BACKGROUND

Yoga is an ancient system of wellness with Asana and Pranayama as its most popular and propagated modules for management of lifestyle disorders.

OBJECTIVES

The aim of the study was to characterise the liver abnormalities, biochemical changes, and stress levels after Yoga intervention in prediabetic females.

MATERIALS AND METHODS

37 females were randomly divided into Yoga practising and non-practising control groups. The Yoga practising group performed Diabetic Yoga Protocol (DYP) for 3 months. Parameters including size of liver, fatty infiltration, and grade of severity were measured using ultrasonography along with biochemical parameters and stress levels at baseline and after Yoga practice.

RESULTS

The glycosylated hemoglobin (HbA1c) and glucose levels were found significantly reduced in prediabetic (p = 0.015) women after practising DYP, although cholesterol levels increased in menopausal women. No escalation of fatty liver was noted among women practising DYP.

CONCLUSION

DYP reduced the HbA1c and stress levels and therefore, could be a cost-effective tool for preventing prediabetes to diabetes progression.

Nonalcoholic fatty liver disease in obese adolescent females is associated with multi-tissue insulin resistance and visceral adiposity markers

Objective

Nonalcoholic fatty liver disease (NAFLD) is associated with insulin resistance (IR) and visceral adiposity in adults and boys, but girls with NAFLD are understudied. We sought to evaluate adipose, liver, and skeletal muscle insulin sensitivity in obese adolescent females with or without hepatic steatosis (HS) (intrahepatic triglyceride (IHTG) content >5.5%) along with cardiometabolic components typically associated with IR.

Study design

73 obese adolescent girls at high risk for NAFLD were enrolled. Participants underwent fasting labs, an MRI to measure IHTG and visceral fat, ³¹phosphorous MR spectroscopy for muscle mitochondrial function, ¹H MR spectroscopy for intramyocellular lipid (IMCL), bicycle ergometry to assess VO₂peak and a 4-phase hyperinsulinemic euglycemic clamp with isotope tracers to measure hepatic and peripheral IR. 29 participants had HS [age 15 yrs(13,16), BMI%ile 98.7(97.4,99.0), IHTG 10.4%(8.0,13.5)] and 44 did not [age 15 yrs(13,17), BMI%ile 98.5(96.2,99.0), IHTG 2.0%(1.1,3.0)].

Results

During hyperinsulinemia, participants with HS vs. non-HS had failure to suppress free fatty acids (p = 0.008), endogenous glucose release (p = 0.002), and a lower glucose metabolic rate of disappearance (Rd) (p = 0.012). Girls with NALFD also had higher visceral fat (p < 0.001), systolic blood pressure (p = 0.026), triglycerides (p = 0.02), ALT (p < 0.01) and white blood cell count (p < 0.01), and lower adiponectin (p = 0.02). There was no difference between girls with and without HS in systemic glycerol turnover measured with glycerol release, or in IMCL, mitochondrial function or VO₂peak.

Conclusions

Obese adolescent girls with HS have evidence of multi-tissue IR, visceral adiposity, inflammation and multiple components of the metabolic syndrome, arguing for close cardiometabolic surveillance over time of girls with HS.

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We described tissue specific insulin sensitivity in adolescent girls ± NAFLD.

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Girls with NAFLD have higher hepatic and muscular insulin resistance.

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Intramyocellular lipids and muscle mitochondrial function were not different between groups.

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Adipose tissue insulin resistance was not different between groups.

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Girls with NAFLD have worst metabolic profile than those without.

Association of OPG-RANKL ratio with left ventricular hypertrophy and geometric remodeling in male overweight/obese youths

PURPOSE

Receptor activator of nuclear factor kappa B ligand/receptor activator of nuclear factor kappa B/osteoprotegerin (RANKL/RANK/OPG) axis has been hypothesized as a potential mediator of left ventricular hypertrophy (LVH). The aim of the study was to assess whether circulating concentrations of RANKL, RANK, and OPG were associated with early signs of morphological cardiac changes in overweight/obese youths.

METHODS

We determined serum levels of RANKL, RANK and OPG by enzyme-linked immunosorbent assays in 188 overweight/obese children and adolescents. LV mass index (LVMI) and relative wall thickness (RWT) were estimated using M-mode echocardiography.

RESULTS

OPG and RANKL levels were higher among girls than among boys [1.73 (1.64-1.86) and 3.28 (1.90-6.37) pmol/L, respectively, vs. 1.69 (1.59-1.82) and 2.12 (1.52-3.80) pmol/L; p = 0.02 and p = 0.0001, respectively], but the OPG/RANKL ratio was lower [0.52 (0.26-0.88) vs 0.77 (0.44-1.11); p = 0.001]. In gender-specific multivariate linear regression, OPG/RANKL ratio was associated with LVMI and RWT in boys but not in girls. In multiple logistic regression, after adjustment for clinical variables, OPG/RANKL ratio was associated with concentric remodeling, eccentric and concentric LVH in boys but not in girls.

CONCLUSION

OPG/RANKL ratio is independently associated with LVH and patterns of LV structural remodeling in male overweight/obese children and adolescents.

Relation of the degree of obesity in childhood to adipose tissue insulin resistance

AIMS

In this study, we investigated whether adipose tissue insulin resistance (IR) is affected by the degree of obesity during the fasting and post-prandial state, independent of glucose tolerance among obese children and adolescents. We also tested whether systemic subclinical inflammation is associated with adipose tissue IR.

METHODS

Subjects were recruited to the Yale Pathophysiology of Type 2 Diabetes in Youth Study (NCT01967849). An oral glucose-tolerance test was performed to establish glucose-tolerance status and blood samples were drawn for measurement of free fatty acids (FFAs), to calculate the area under the curve (AUC) of FFA. Adipose tissue insulin resistance was calculated as the product of insulin and FFA concentrations.

RESULTS

In total, 671 children and adolescents (58.6% females) were included with a mean age of 13.3(2.7) years and BMI Z score of 2.45(0.31). The degree of obesity emerged as an independent predictor of both fasting and post-prandial adipose IR, p < 0.0001. Higher degree of obesity was associated with greater AUC FFA (lower suppression) compared to lower degree of obesity, p = 0.01. Furthermore, higher levels of IL-6 were positively associated with post-prandial adipose tissue IR, p = 0.02.

CONCLUSIONS

The degree of obesity in childhood and adolescence is strongly associated with adipose tissue IR independent of glucose tolerance. This is reflected not only in calculated indices of adipose IR but also in lower suppression of FFAs during the OGTT regardless of glucose tolerance or fasting adipose tissue IR. Furthermore, markers of subclinical inflammation such as IL-6 are associated with adipose tissue IR, independent of other factors.

Plant-Derived Oleanolic Acid (OA) Ameliorates Risk Factors of Cardiovascular Diseases in a Diet-Induced Pre-Diabetic Rat Model: Effects on Selected Cardiovascular Risk Factors

The pathogenesis of prediabetes is associated with risk factors such as chronic consumption of an unhealthy diet. Recent studies have reported that diet-induced pre-diabetes is also associated with risk factors of cardiovascular complications, hence this study was aimed at evaluating the effects of oleanolic acid (OA) on pre-diabetes rats. Pre-diabetes was induced by chronic exposure of Sprague Dawley rats (SD) to high-fat high-carbohydrate diet (20 weeks), whereas the non-pre-diabetes control (NC) was given standard rat chow. Pre-diabetes animals were grouped into five groups namely prediabetes control (PC), metformin treated (Met), metformin with diet intervention (Met + DI), oleanolic acid treated (OA), and oleanolic acid with diet intervention (OA + DI) then treated for 12 weeks. At the end of treatment, all animals were sacrificed where organs and tissues were harvested for biochemical analysis and histological studies. The results showed that PC had a significantly higher triglycerides (TGs), low density lipoprotein cholesterol (LDL-C, interleukin-6(IL-6), tumor necrosis factor alpha (TNFα), C-reactive protein (CRP), mean arterial pressure (MAP) and hearts weights in comparison to NC (p < 0.05). However, the administration of OA, in both the presence and absence of dietary intervention showed a significant decrease in TGs, LDL-C, IL-6, TNFα, CRP, MAP, hearts weights (p < 0.05). In conclusion, the administration of OA was able to lower the risks of developing CVDs in pre-diabetes rat model through ameliorating dyslipidaemia, oxidative stress, hypertension, and low-grade inflammation. Therefore OA has the potential to be used as an alternative treatment to prevent the onset of CVDs during pre-diabetes stage even in the absence of dietary and lifestyle intervention.

The Liver in Children With Metabolic Syndrome

Non-alcoholic fatty liver disease (NAFLD) is recognized as an emerging health risk in obese children and adolescents. NAFLD represents a wide spectrum of liver conditions, ranging from asymptomatic steatosis to steatohepatitis. The growing prevalence of fatty liver disease in children is associated with an increased risk of metabolic and cardiovascular complications. NAFLD is considered the hepatic manifestation of Metabolic Syndrome (MetS) and several lines of evidence have reported that children with NAFLD present one or more features of MetS. The pathogenetic mechanisms explaining the interrelationships between fatty liver disease and MetS are not clearly understood. Altough central obesity and insulin resistance seem to represent the core of the pathophysiology in both diseases, genetic susceptibility and enviromental triggers are emerging as crucial components promoting the development of NAFLD and MetS in children. In the present review we have identified and summarizied studies discussing current pathogenetic data of the association between NAFLD and MetS in children.

Advances in Pediatric Fatty Liver Disease: Pathogenesis, Diagnosis, and Treatment

Pediatric nonalcoholic fatty liver disease is an increasingly prevalent disease, but its pathophysiology is not fully elucidated, diagnosis is difficult and invasive, and therapeutic options are limited. This article addresses the recent advancements made in understanding the pathophysiology of nonalcoholic fatty liver disease, the development of less invasive diagnostic modalities, and emerging therapeutic options, including ongoing clinical trials in children.

Body Adiposity Index and Body Roundness Index in Identifying Insulin Resistance Among Adults Without Diabetes

BACKGROUND

Body adiposity index (BAI) and body roundness index (BRI), initially developed to assess obesity, were evaluated here to detect insulin resistance in comparison with traditional anthropometric indices of body mass index (BMI), waist circumference (WC), weight-to-height ratio (WHtR), visceral adiposity index (VAI) and abdominal volume index (AVI).

METHODS

In this cross-sectional study, 570 Chinese individuals without diabetes were evaluated.

RESULTS

The Spearman rank test showed that insulin resistance correlated most strongly with WC and AVI in men and BMI in women, and most weakly with BAI in men and VAI in women. The prevalence of insulin resistance increased per quartile for all 7 anthropometric indices. Multivariate logistic regression identified BAI as the weakest predictor of insulin resistance in both genders (men, odds ratio [OR] 3.34, 95% confidence interval [CI] 1.09-10.18; women, OR 4.90, 95% CI 1.89-12.69), AVI as the strongest predictor in men (OR 19.73, 95% CI 2.51-155.04) and BMI as the strongest predictor in women (OR 15.55, 95% CI 4.71-51.28). The area under the receiver operating characteristic curve (AUC) showed that BAI exhibited the lowest AUCs for men (0.653, 95% CI 0.574-0.731) and women (0.701, 95% CI 0.627-0.774). BRI showed significantly higher AUCs for men (0.769, 95% CI 0.699-0.838) and women (0.763, 95% CI 0.699-0.827), and WHtR showed equal AUCs to BRI.

CONCLUSIONS

Neither BAI nor BRI were superior to BMI, WC, WHtR, VAI or AVI for predicting insulin resistance. BAI showed the weakest predictive ability, while BRI showed reasonable potential to serve as an alternative anthropometric index to detect insulin resistance.

Body composition analysis and references in children: clinical usefulness and limitations

The prevalence of obesity is increasing over the world. Especially in Asians compared to Caucasians, there has been a significant increase in the population with major chronic diseases. This has developed over a shorter time period which is associated with socioeconomic changes in recent decades and a greater predisposition to cardiometabolic disorders. Many Asians could be classified has having normal weight but with obesity as evidenced by body composition (BC) and fat distribution. Overweight in Asian adults is classified as a BMI > 23 kg/m² and obesity as a BMI > 25 kg/m². An effective strategy to manage the obesity epidemic by focusing on childhood obesity is needed because of the huge impact that obesity exerts on population health. However, monitoring tools are limited to anthropometry such as BMI and BMI z-scores which define overweight and obese as a BMI exceeding the 85th and 95th percentiles, respectively, on reference growth charts. To overcome the limitations of BMI, reference values for BC components have been produced using various techniques. The use of BC charts for children in personalized therapeutic approach has increased, although there is a lack of a consensus on a single reference technique. Zones on BC charts and the personalized values of BC components could be practical, especially for the detection of metabolically unhealthy normal weight (MUN) children. BC charts should be included in the growth chart package and BC monitoring through the entire life course will help us understand the association between growth, aging, health and disease.

Hepatic lesions induced by feeding Western diets to Zucker fatty rats, an insulin-resistant model

Metabolic diseases including nonalcoholic steatohepatitis develop due to various environmental factors. In particular, the westernization of food is closely related to the development of these diseases. In this study, we investigated pathophysiological changes in the livers of Zucker fatty (ZF) rats induced by feeding Western diets. Male ZF rats were fed a sucrose/fat/cholesterol-enriched diet (Western diet, WD) or standard diet (SD) for 18 weeks, from 7 to 25 weeks of age. Body weight, food intake, and biochemical parameters were periodically measured, histopathological analyses were performed at 25 weeks, and mRNA expression in the liver was determined. ZF rats fed the WD (ZF-WD rats) developed obesity, hyperinsulinemia, hyperglycemia, and hyperlipidemia, and their alanine aminotransferase and aspartate aminotransferase levels increased compared with those of ZF rats fed the SD (ZF-SD rats). Hepatic lesions including fibrosis and necrosis were observed in the ZF-WD rats at 25 weeks; however, fibrosis and necrosis were not observed in the ZF-SD rats. Oxidative stress markers also increased in the livers of ZF-WD rats. Hepatic mRNA expression related to inflammation and fibrosis increased in the ZF-WD rats; however, mRNA expression related to lipid synthesis decreased. Microsomal triglyceride transfer protein mRNA levels in the ZF-WD rats also decreased. In Zucker lean rats fed the WD, similar changes were observed in the liver; however, the hepatic changes were not serious compared with ZF-WD rats. In conclusion, hepatic lesions, such as inflammation, fibrosis, and necrosis, were observed in the ZF-WD rats. The sucrose/fat/cholesterol-enriched diet induced significant lipotoxicity in the livers of animals in this insulin-resistant model.

Carbohydrates and diet patterns in nonalcoholic fatty liver disease in children and adolescents

PURPOSE OF REVIEW

The primary treatment for nonalcoholic fatty liver disease (NAFLD) in children is lifestyle change, including a healthier diet. However, there are no agreed upon expert recommendations for a specific diet in the prevention or treatment of NAFLD. In this study, we review studies published between 2015 and 2017 contributing to further understanding of the role of diet in the development and progression of NAFLD, particularly those addressing sugars and dietary patterns.

RECENT FINDINGS

Multiple recent studies have expanded on earlier evidence that suggests that high intake of sugars plays a causal role in the development of NAFLD, including several recent experimental studies in adults and children that support a unique effect of fructose consumption on liver fat accumulation. Evidence also points to protective effects of dietary patterns that include but are not limited to minimizing sugar intake, Dietary Approaches to Stop Hypertension (DASH), high protein and the Mediterranean diet. The effect of diet may act through its impact on the microbiome, and may be modified by presence or absence of genetic polymorphisms (nutrigenomics) and several new studies demonstrate this.

SUMMARY

Diet appears to be a powerful tool in the prevention and treatment of NAFLD. It is imperative that researchers and clinicians continue to hone in on the mechanistic pathways and specific diets to reverse the growing morbidity and mortality of NAFLD.

Promotive effect of Bofutsushosan (Fangfengtongshengsan) on lipid and cholesterol excretion in feces in mice treated with a high-fat diet

ETHNOPHARMACOLOGICAL RELEVANCE

Bofutsushosan (fangfengtongshengsan in Chinese, BTS) is a formula in traditional Japanese Kampo medicine and Chinese medicine comprising 18 crude drugs that is used for treating obesity and metabolic syndrome.

AIM OF THE STUDY

We evaluated the promotive effects of BTS on lipid and cholesterol elimination in mice.

MATERIALS AND METHODS

Mice were reared with a high-fat diet containing boiled water extract of BTS for 30 days, and their biochemical parameters as well as the weight and lipid content of feces were measured. We also measured cholesterol uptake into Caco-2 cells cultured with or without BTS extract.

RESULTS

The body weight and amounts of visceral fat and subcutaneous fat on day 28; the weights of epididymal, perirenal, and mesenteric fat; and the serum concentrations of triglyceride, glucose, and hemoglobin A1c on day 30 were significantly lower in the BTS extract-treated groups than in the control in a dose-dependent manner. The amounts of lipid and cholesterol in the feces collected from day 6-23 were significantly greater than in the control. When Caco-2 cells were incubated with BTS extract, the uptake of cholesterol into cells was significantly reduced in a concentration-dependent manner. Among the components of BTS, the methanol extracts of Platycodi Radix and Zingiberis Rhizoma contribute but the extracts of Ephedrae Herba and Rhei Rhizoma counteract the suppressive effect of BTS on cholesterol uptake into Caco-2 cells.

CONCLUSIONS

BTS has beneficial effects on obesity and metabolic syndrome, and its mechanisms of action include the promotion of lipid elimination and the inhibition of cholesterol absorption in the intestine.

Obesity-Related Metabolic Risk in Sedentary Hispanic Adolescent Girls with Normal BMI

Hispanic adolescent girls with normal BMI frequently have high body fat %. Without knowledge of body fat content and distribution, their risk for metabolic complications is unknown. We measured metabolic risk indicators and abdominal fat distribution in post-pubertal Hispanic adolescent girls with Normal BMI (N-BMI: BMI < 85th percentile) and compared these indicators between girls with Normal BMI and High Fat content (N-BMI-HF: body fat ≥ 27%; n = 15) and Normal BMI and Normal Fat content (N-BMI-NF: body fat < 27%; n = 8). Plasma concentrations of glucose, insulin, adiponectin, leptin and Hs-CRP were determined. Insulin resistance was calculated using an oral glucose tolerance test. Body fat % was measured by DXA and subcutaneous, visceral and hepatic fat by MRI/MRS. The N-BMI-HF girls had increased abdominal and hepatic fat content and increased insulin resistance, plasma leptin and Hs-CRP concentrations (p < 0.05) as compared to their N-BMI-NF counterparts. In N-BMI girls, insulin resistance, plasma insulin and leptin correlated with BMI and body fat % (p < 0.05). This research confirms the necessity of the development of BMI and body fat % cut-off criteria per sex, age and racial/ethnic group based on metabolic risk factors to optimize the effectiveness of metabolic risk screening procedures.

Treatment of adolescent obesity

The increased prevalence of adolescent obesity and associated short-term and long-term complications emphasize the need for effective treatment. In this Review, we aim to describe the evidence for, and elements of, behaviour management and adjunctive therapies and highlight the opportunities and challenges presented by obesity management in adolescence. The broad principles of treatment include management of obesity-associated complications; a developmentally appropriate approach; long-term behaviour modification (dietary change, increased physical activity, decreased sedentary behaviours and improved sleep patterns); long-term weight maintenance strategies; and consideration of the use of pharmacotherapy, more intensive dietary therapies and bariatric surgery. Bariatric surgery should be considered in those with severe obesity and be undertaken by skilled bariatric surgeons affiliated with teams experienced in the medical and psychosocial management of adolescents. Adolescent obesity management strategies are more reliant on active participation than those for childhood obesity and should recognize the emerging autonomy of the patient. The challenges in adolescent obesity relate primarily to the often competing demands of developing autonomy and not yet having attained neurocognitive maturity.

The "adipose tissue expandability" hypothesis: a potential mechanism for insulin resistance in obese youth

Obesity has become a major global health challenge of the 21st century, as it is associated with the onset of type 2 diabetes (T2D) and cardiovascular complications, even at a very early age in life. The root causes of pediatric obesity remain incompletely understood. The obesity epidemic together with the relationship of obesity to the growing population burden of chronic disease presents unprecedented research opportunities and challenges. Decades of obesity-related research funded by governments around the world have yielded many important discoveries about both etiological pathways and preventive or therapeutic interventions. Yet, there is a sense that the problem is outpacing these research efforts. Obesity poses a significant risk for the development of cardiovascular disease (CVD) , diabetes and certain cancers thereby shortening life expectancy. Nevertheless, many obese individuals do not develop any of these comorbidities. One hypothesis explaining this dilemma is that total body fat is not the culprit of adverse health in obesity rather the relative proportion of lipids in various fat depots is what determines the metabolic risk. In this review, we describe the role of altered fat partitioning in youth onset obesity and its relation to fatty liver and T2D during adolescence.

The role of NAFLD in cardiometabolic disease: an update

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in the world, yet the complex pathogenesis remains to be fully elucidated. The prevalence of NAFLD has risen precipitously in recent years and is now a leading indication for liver transplantation. New waitlist registrants with non-alcoholic steatohepatitis–induced cirrhosis increased by 170% from 2004 to 2013. In addition, patients with NAFLD are at increased risk of both cardiovascular disease and type II diabetes. In this update, recent studies contributing to the understanding of the place of NAFLD in cardiometabolic disease will be discussed.

[Correlation between ectopic fat accumulation and insulin sensitivity in obese individuals with different glucose tolerance levels]

OBJECTIVE

To investigate the correlation between liver and skeletal muscle fat contents and insulin resistance in obese individuals with different levels of glucose tolerance.

METHODS

RESULTS: Ten non-obese individuals with normal glucose tolerance (NGT), 9 obese individuals with NGT, and 7 obese individuals with impaired glucose tolerance (IGT) were enrolled in this study. All the participants were examined for insulin sensitivity by hyperinsulinemic-euglycemic clamp and for liver and skeletal muscle fat accumulation quantified by proton magnetic resonance spectroscopy (1H MRS). The data were collected from the subjects including somatometric measurements, fasting plasma glucose, 2-h plasma glucose (2hPG), fasting insulin, and blood biochemistry. Linear correlation analysis and multiple linear stepwise regression analysis were used to analyze the relationship between ectopic fat accumulation and insulin resistance.

RESULTS

The glucose infusion rates (GIR, presented as the M value) differed significantly among IGT-obese (3.95∓1.66 mg·kg^-1·min^-1), NGT-obese (6.14∓1.90 mg·kg^-1·min^-1) and NGT-non-obese (8.78∓2.46 mg·kg^-1·min^-1) groups (P<0.05). The 3 groups also showed significant differences in liver fat contents [(15.23∓3.09)%, (6.25∓0.38)%, and (1.89∓0.90)%, respectively, P<0.05] and intramyocellular lipids in the tibialis anterior (2.69∓0.95, 2.61∓1.45, and 1.54∓0.66 mmol/kg, respectively, P<0.05). Linear analysis revealed that liver fat content, but not skeletal muscle fat content, was significantly correlated with the M value. Multiple linear stepwise regression analysis using M value as the dependent variable (Y) revealed that liver fat content (X) was an independent factor inversely correlated with the M value (regression equation: Y=-30.562X+9.007, R²=0.717, P<0.01).

CONCLUSIONS

Liver fat accumulation, but not skeletal muscle fat accumulation, is correlated with insulin resistance and impaired glucose metabolism.

Insulin Resistance and NAFLD: A Dangerous Liaison beyond the Genetics

Over the last decade, the understanding of the association between insulin resistance (IR) and non-alcoholic fatty liver disease (NAFLD) has dramatically evolved. There is clear understanding that carriers of some common genetic variants, i.e., the patatin-like phospholipase domain-containing 3 (PNPLA3) or the transmembrane 6 superfamily member 2 (TM6SF2) are at risk of developing severe forms of NAFLD even in the presence of reduced or absent IR. In contrast, there are obese patients with “metabolic” (non-genetically driven) NAFLD who present severe IR. Owing to the epidemic obesity and the high prevalence of these genetic variants in the general population, the number of pediatric cases with combination of genetic and metabolic NAFLD is expected to be very high. Gut dysbiosis, excessive dietary intake of saturated fats/fructose-enriched foods and exposure to some chemicals contribute all to both IR and NAFLD, adding further complexity to the understanding of their relationship. Once NAFLD is established, IR can accelerate the progression to the more severe form of liver derangement that is the non-alcoholic steatohepatitis.