Weight loss, inflammatory markers, and improvements of iron status in overweight and obese children

Association between Serum Ferritin Levels and Metabolic-associated Fatty Liver Disease in Adults: a Cross-sectional Study Based on the NHANES

OBJECTIVE

Ferritin, initially acting as an iron-storage protein, was found to be associated with metabolic diseases. Our study was designed to investigate the association between serum ferritin and metabolic-associated fatty liver disease (MAFLD) using data from the National Health and Nutrition Examination Survey (NHANES) of the United State of America.

METHODS

A cross-sectional study was conducted, enrolling a total of 2145 participants from the NHANES in the 2017-2018 cycles. Hepatic steatosis and liver fibrosis were assessed by ultrasound images and several non-invasive indexes. Multiple regression analysis was conducted to determine the associations between serum ferritin concentration and MAFLD and liver fibrosis.

RESULTS

The analysis revealed that participants with higher serum ferritin levels (Q3 and Q4 groups) had a higher prevalence of MAFLD than those with the lowest serum ferritin levels [Q3 vs. Q1: OR=2.17 (1.33, 3.53), P<0.05 in fatty liver index (FLI); Q4 vs. Q1: OR=3.13 (1.91, 5.13), P<0.05 in FLI]. Additionally, participants with the highest serum ferritin levels (Q4 group) displayed a higher prevalence of liver fibrosis [Q4 vs. Q1: OR=2.59 (1.19, 5.62), P<0.05 in liver stiffness measurement; OR=5.06 (1.12, 22.94), P<0.05 in fibrosis-4 index], with significantly increased risk observed in participants with concomitant diabetes [OR=7.45 (1.55, 35.72), P=0.012].

CONCLUSION

Our study revealed that elevated serum ferritin levels are associated with a higher prevalence of MAFLD and advanced liver fibrosis in patients. Elevated serum ferritin levels combined with diabetes are important risk factors for liver fibrosis.

Associations of Serum Iron Status with MAFLD and Liver Fibrosis in the USA: a Nationwide Cross-Section Study

Metabolic dysfunction-associated fatty liver disease (MAFLD) is a new terminology characterized by liver steatosis. Iron status is related to many metabolic diseases. However, the researches on the associations of serum iron status with MAFLD are limited. The objective of this study was to investigate the associations of serum iron status biomarkers with MAFLD and liver fibrosis. A total of 5892 adults were enrolled in the current cross-sectional study using the 2017-March 2020 National Health and Nutrition Examination Survey. Liver steatosis and liver fibrosis were defined by the median values of controlled attenuation parameter ≥ 274 dB/m and liver stiffness measurement ≥ 8 kPa, respectively. The multivariable logistic/linear regression and restricted cubic spline analysis were conducted. After adjusting for potential confounders, higher ferritin levels were associated with higher odds of MAFLD (OR 4.655; 95% CI 2.301, 9.418) and liver fibrosis (OR 7.013; 95% CI 3.910, 12.577). Lower iron levels were associated with a higher prevalence of MAFLD (OR 0.622; 95% CI 0.458, 0.844) and liver fibrosis (OR 0.722; 95% CI 0.536, 0.974). Lower transferrin saturation (TSAT) was associated with a higher prevalence of MAFLD (OR 0.981; 95% CI 0.970, 0.991) and liver fibrosis (OR 0.988; 95% CI 0.979, 0.998). Higher ferritin levels, lower iron levels, and TSAT were associated with a higher prevalence of MAFLD and liver fibrosis. This study extended the knowledge of modifying iron status to prevent MAFLD and liver fibrosis. More prospective and mechanism studies were warranted to confirm the conclusions.

Improvement of vitamin D status through consumption of either fortified food products or supplement pills increased hemoglobin concentration in adult subjects: Analysis of pooled data from two randomized clinical trials

Background: It is documented that vitamin D may have a role in erythropoiesis as its deficiency is accompanied by an increased risk of anemia. Aim: This study aimed to examine whether improvement of vitamin D status through daily consumption of either fortified foods or supplements could impinge on certain hematologic parameters in adults. Methods: We pooled data from our two separate clinical trials and made five experimental groups. As part of their usual diet, one group consumed 500 mL/day of yogurt drink fortified with 1000 IU of vitamin D (D-yogurt, n = 27) whereas one group consumed 500 mL/day of the plain yogurt drink (P-yogurt, n = 27). In addition three other groups consumed either 50 g/day bread fortified with 1000 IU of vitamin D (D-bread) or supplement containing 1000 IU vitamin D (D-supplement, n = 27) or placebo (placebo, n = 27). Biochemical measurements were performed before and after the intervention. Results: In all three vitamin D-supplemented groups, serum 25(OH)D concentration increased after the intervention period, which was interestingly accompanied by a significant increment of hemoglobin (D-yogurt, p < 0.001, D-bread, p = 0.003, D-supplement, p < 0.001). Analyses indicated that among participants in vitamin D-intervention groups, being in D-yogurt group was more favourable predictor of improvement in hemoglobin concentrations compared with the placebo (p < 0.001), D-bread (p = 0.045) and P-yogurt (p = 0.001). Conclusion: Improvement of vitamin D status via regular intake of either vitamin D-fortified food products or supplements can result in a significant increment of hemoglobin in adult subjects. This finding has very important clinical as well as public health implications.

Micronutrient Deficiency in Children and Adolescents with Obesity-A Narrative Review

Childhood obesity represents a serious public health burden. Despite excessive dietary consumption, children with obesity present high rates of micronutrient deficiencies, such as deficiencies in minerals and specific vitamins; micronutrient deficiencies may have a pathogenic role in obesity-related metabolic comorbidities. In this narrative review, we analyzed the main deficiencies associated with obesity, their clinical consequences, and the evidence about a possible supplementation. Iron; vitamins A, B, C, D, and E; folic acid; zinc; and copper deficiencies represent the most common deficient microelements. The relationship between obesity and multiple micronutrient deficiencies remains unclear, and different mechanisms have been proposed. The medical care plan for pediatric obesity should include food choices with high nutritional content as part of a crucial approach to obesity-related complications. Unfortunately, only a few studies are available regarding the efficacy of oral supplementation or weight loss for treating them; thus, continuous nutritional monitoring is necessary.

Long-Term Outcomes of Iron Deficiency Before and After Bariatric Surgery: a Systematic Review and Meta-analysis

PURPOSE

This study reviews the prevalence of iron deficiency (ID) in bariatric surgery candidates and the long-term outcomes of the prevalence of ID after bariatric surgery.

MATERIALS AND METHODS

A systematic literature search and meta-analysis were performed in PubMed for articles published by August 31, 2022, including these search terms: bariatric surgery, metabolic surgery, weight loss surgery, obesity surgery, sleeve gastrectomy, gastric banding, gastric bypass, duodenal switch, duodenojejunal bypass, iron, iron deficiency, sideropenia, and hypoferritinemia. Fifty-seven studies examining a total of 26,328 patients with morbidly obese were included in this meta-analysis finally.

RESULTS

The results showed a prevalence of 17% of ID in bariatric surgery candidates and a prevalence of 14%, 17%, 26%, 34%, 23%, 38%, and 23% of ID at 1-, 2-, 3-, 4-, 5-, 8-, and 10-year follow-up after bariatric surgery, respectively. Additionally, the results showed a prevalence of 15%, 19%, 35%, 38%, 29%, 30%, and 23% of ID at 1-, 2-, 3-, 4-, 5-, 8-, and 10-year follow-up after Roux-en-Y gastric bypass, respectively; a prevalence of 12%, 12%, 15%, 31%, and 17% of ID at 1-, 2-, 3-, 4-, and 5-year follow-up after sleeve gastrectomy, respectively; and a prevalence of 19% of ID at 1-year follow-up after anastomosis gastric bypass.

CONCLUSION

As a result, preoperative evaluation and correction of ID may lead to better outcomes for bariatric surgery candidates. ID is also common in patients after bariatric procedures, especially RYGB. Long-term, even lifelong, medical and nutritional monitoring and tailored interventions are critical.

Impact of resistance training and basic ferritin on hepcidin, iron status and some inflammatory markers in overweight/obese girls

BACKGROUND

Exercise can reduce hepcidin, tumor necrosis factor (TNF)-α, and interleukin (IL)-6 and improve the iron status, but the intensity of exercises is very important. This study will compare the effect of resistance training (RT) intensity on hepcidin levels, iron status, and inflammatory markers in overweight/obese girls with and without iron stores deficient.

MATERIALS AND METHODS

In this quasi-experimental study, 40 students of the University of Isfahan (18-22-year old, with 35 > body mass index [BMI] ≥25) voluntarily participated in the study. Participants were divided into two groups with 20 participants, based on serum ferritin (>30 ng/ml or ≤30 ng/ml). Participants in each group were randomly and equally assigned to one of the moderate or high-intensity training groups. RT was performed 8 weeks, 4 days a week, and each session for 1 h, with an elastic band. The iron levels, hepcidin, total iron-binding capacity, ferritin, hemoglobin, TNF-α, and IL-6 before and after intervention were collected with the blood samples. Two-way analysis of variance was used to assess the impact of exercise and ferritin level and their interaction, and the paired test was utilized for test changes from baseline.

RESULTS

There are no significant interactions between ferritin levels and exercise intensity for the main outcomes (all P > 0.05). The significant impact of the mode of exercise was observed in TNF-α (P < 0.05), and a significant difference between low and high levels of ferritin was observed in hepcidin (P = 0.002). Besides, in all four groups, significant decreases were observed in BMI (28.00 ± 3.00 to 27.00 ± 3.00), hepcidin (1234.02 ± 467.00 to 962.06 ± 254.00), and TNF-α (223.00 ± 99.00 to 174.00 ± 77.00) compared to the baseline measurements (all P < 0.05).

CONCLUSION

Basal ferritin levels appear to be effective on hepcidin levels, TNF-α, and IL-6 after the intervention. RT with two different intense can reduce BMI, hepcidin, ferritin, and TNF-α in all groups. It seems that performing RT reduces inflammation and hepcidin in obese/overweight participants with different iron stores.

Association between obesity and iron deficiency (Review)

Obesity is a risk factor for several comorbidities and complications, including iron deficiency anemia. Iron deficiency anemia is a serious global public health problem, with a worldwide prevalence. The high prevalence of obesity in combination with iron deficiency incidence observed in different age and sex categories suggests an association between obesity and iron status. Obesity may disrupt iron homeostasis, resulting in iron deficiency anemia. The association between obesity and iron deficiency may be due to increased hepcidin levels mediated by chronic inflammation. Hepcidin is a small peptide hormone that functions as a negative regulator of intestinal iron absorption. Significant body weight loss in overweight and obese individuals decreases chronic inflammation and serum hepcidin levels, resulting in improved iron status due to increased iron absorption. However, further randomized controlled trials are required to confirm this effect.

Iron supplementation regulates the progression of high fat diet induced obesity and hepatic steatosis via mitochondrial signaling pathways

Disruption of iron metabolism is closely related to metabolic diseases. Iron deficiency is frequently associated with obesity and hepatic steatosis. However, the effects of iron supplementation on obesity and energy metabolism remain unclear. Here we show that a high-fat diet supplemented with iron reduces body weight gain and hepatic lipid accumulation in mice. Iron supplementation was found to reduce mitochondrial morphological abnormalities and upregulate gene transcription involved in mitochondrial function and beta oxidation in the liver and skeletal muscle. In both these tissues, iron supplementation increased the expression of genes involved in heme or iron–sulfur (Fe–S) cluster synthesis. Heme and Fe–S cluster, which are iron prosthetic groups contained in electron transport chain complex subunits, are essential for mitochondrial respiration. The findings of this study demonstrated that iron regulates mitochondrial signaling pathways—gene transcription of mitochondrial component molecules synthesis and their energy metabolism. Overall, the study elucidates the molecular basis underlying the relationship between iron supplementation and obesity and hepatic steatosis progression, and the role of iron as a signaling molecule.

Iron Deficiency in Obesity and after Bariatric Surgery

Iron deficiency (ID) is particularly frequent in obese patients due to increased circulating levels of acute-phase reactant hepcidin and adiposity-associated inflammation. Inflammation in obese subjects is closely related to ID. It induces reduced iron absorption correlated to the inhibition of duodenal ferroportin expression, parallel to the increased concentrations of hepcidin. Obese subjects often get decreased inflammatory response after bariatric surgery, accompanied by decreased serum hepcidin and therefore improved iron absorption. Bariatric surgery can induce the mitigation or resolution of obesity-associated complications, such as hypertension, insulin resistance, diabetes mellitus, and hyperlipidemia, adjusting many parameters in the metabolism. However, gastric bypass surgery and sleeve gastrectomy can induce malabsorption and may accentuate ID. The present review explores the burden and characteristics of ID and anemia in obese patients after bariatric surgery, accounting for gastric bypass technique (Roux-en-Y gastric bypass-RYGB) and sleeve gastrectomy (SG). After bariatric surgery, obese subjects' iron status should be monitored, and they should be motivated to use adequate and recommended iron supplementation.

Iron Fortification and Supplementation: Fighting Anemia of Chronic Diseases or Fueling Obesity?

The significant worldwide increase in obesity has become a major health problem. Excess adiposity has been extensively linked to inflammation. Recently, studies have shown that dietary intake and microbiota dysbiosis can affect the health of the gut and lead to low-grade systemic inflammation, worsening the state of obesity and further exacerbating inflammation. The latter is shown to decrease iron status and potentially increase the risk of anemia by inhibiting iron absorption. Hence, anemia of obesity is independent of iron intake and does not properly respond to increased iron ingestion. Therefore, countries with a high rate of obesity should assess the health impact of fortification and supplementation with iron due to their potential drawbacks. This review tries to elucidate the relation between inflammation and iron status to better understand the etiology of anemia of obesity and chronic diseases and wisely design any dietary or medical interventions for the management of anemia and/or obesity.

Profiles of anemia among school-aged children categorized by body mass index and waist circumference in Shandong, China

BACKGROUND

The prevalence of childhood obesity has been increasing worldwide. The connection between iron deficiency and obesity has received much research interest. The present study examined the profiles of anemia among school-aged children categorized by obesity-related index in Shandong, China.

METHODS

A total of 20,172 children aged 7, 9, 12, and 14 years participated in the study, whose hemoglobin (Hb) concentration was measured by laboratory technicians. The prevalence rates of anemia among children within each subgroup categorized by body mass index (BMI), waist circumference (WC) and waist-to-height ratio (WHtR) were determined.

RESULTS

On the whole, 3.99% of boys and 6.68% of girls suffer from anemia. Disparities in the prevalence of anemia were observed between different subgroups categorized by BMI, WC and WHtR. For both boys and girls, the prevalence of anemia increased with the severity of thinness and obesity, suggesting that both severe thinness and severe obesity are associated with an elevated prevalence of anemia.

CONCLUSION

In the era of the obesity pandemic, obesity could potentially add to the burden of anemia, suggesting that obese children should not be ignored when establishing strategies targeted at preventing anemia.

Can diet-induced weight loss improve iron homoeostasis in patients with obesity: A systematic review and meta-analysis

Despite the increasing worldwide prevalence of obesity and iron deficiency (ID), there are still no guidelines on how to treat and manage obesity-related ID. The aim of this systematic review and meta-analysis was to investigate whether weight loss can re-establish iron homoeostasis among subjects with unhealthy weight (overweight [OW] or obesity). PubMed, Medline, Embase, Web of Science, and the Cochrane Library were systemically searched for studies that compared the iron status before and after a weight-loss intervention. A random-effects model was used to calculate the pooled and subgroup weighted mean differences (WMDs) of iron biomarkers. In total, 879 subjects were pooled across 14 studies. Improved haemoglobin was found in longitudinal studies (WMD = 2.50 g/dl, 95% confidence interval [CI]: 0.88, 4.12 g/dl, I² = 14%) but not in randomized controlled trials or after being stratified by dietary programmes. Significantly increased transferrin saturation was observed in pooled (WMD = 1.68%, 95% CI: 0.97%, 2.39%, I² = 44%) and subgroup analyses. A meta-regression showed that changes in the iron status were positively correlated with changes in the body mass index (BMI) and the intervention duration but negatively correlated with the baseline body weight/BMI, age, gender and a standard hypocaloric diet. Our data suggested that in spite of energy restrictions, weight loss may help re-establish iron homoeostasis in people who are OW or obese.

Chronic intermittent hypobaric hypoxia improves markers of iron metabolism in a model of dietary-induced obesity

BACKGROUND

Obesity, a risk factor for many chronic diseases, is a potential independent risk factor for iron deficiency. Evidence has shown that chronic intermittent hypobaric hypoxia (CIHH) has protective or improved effects on cardiovascular, nervous, metabolic and immune systems. We hypothesized that CIHH may ameliorate the abnormal iron metabolism in obesity. This study was aimed to investigate the effect and the underlying mechanisms of CIHH on iron metabolism in high-fat-high-fructose-induced obese rats.

METHODS

Six to seven weeks old male Sprague-Dawley rats were fed with different diet for 16 weeks, and according to body weight divided into four groups: control (CON), CIHH (28-day, 6-h daily hypobaric hypoxia treatment simulating an altitude of 5000 m), dietary-induced obesity (DIO; induced by high fat diet and 10% fructose water feeding), and DIO + CIHH groups. The body weight, systolic arterial pressure (SAP), Lee index, fat coefficient, blood lipids, blood routine, iron metabolism parameters, interleukin6 (IL-6) and erythropoietin (Epo) were measured. The morphological changes of the liver, kidney and spleen were examined. Additionally, hepcidin mRNA expression in liver was analyzed.

RESULTS

The DIO rats displayed obesity, increased SAP, lipids metabolism disorders, damaged morphology of liver, kidney and spleen, disturbed iron metabolism, increased IL-6 level and hepcidin mRNA expression, and decreased Epo compared to CON rats. But all the aforementioned abnormalities in DIO rats were improved in DIO + CIHH rats.

CONCLUSIONS

CIHH improves iron metabolism disorder in obese rats possibly through the down-regulation of hepcidin by decreasing IL-6 and increasing Epo.

Serum phytosterols associate with T helper 1 cytokine concentration in pregnant women

The dietary phytosterols have been demonstrated to modulate CD4+ T-cell polarization in cells, animals, and humans. However, T helper (Th)1/Th2 dichotomy has rarely been correlated with phytosterols during pregnancy. The present study investigated associations between the serum cytokines and serum phytosterols in 100 pregnant women at 34- to 37-week gestation and their offspring. The results showed that serum concentrations of interferon (IFN)-γ, tumor necrosis factor (TNF)-α, and total Th1 cytokines were positively associated with serum β-sitosterol level, adjusting for age, BMI, and serum cholesterol. Serum IFN-γ and total Th1 cytokine concentrations positively correlated with total phytosterol concentration, controlling age, BMI, and serum cholesterol. Moreover, none of the cytokines measured correlated with phytosterol concentration in the newborns. Our results show that serum Th1 cytokine concentrations, but not Th2 levels, are positively associated with serum phytosterols in pregnant women. These findings implicate that phytosterols modulate Th1/Th2 balance by inducing Th1 secretions in pregnant women.

A Multidisciplinary Intervention in Childhood Obesity Acutely Improves Insulin Resistance and Inflammatory Markers Independent From Body Composition

Childhood obesity is an increasing health care problem associated with insulin resistance and low-level systemic inflammation, which can ultimately lead to diabetes. Evidence for efficacy of therapeutic intervention programs on the early development of obesity associated sequelae is moderate. This paper investigates the effect of a multidisciplinary short-term intervention program on insulin resistance and metaflammation in childhood obesity. Two hundred and 36 overweight or obese children and adolescents between the ages of 10 and 14 were included in a prospective 5 months intervention study, which included sports, psychotherapy, and nutritional counseling. Primary endpoints were the effects on body mass index standard deviation score (BMI-SDS) and homeostatic model assessment of insulin resistance (HOMA-IR), key secondary endpoints were the levels of C-reactive protein (CRP), leptin, and adiponectin. At baseline, a substantial proportion of participants showed signs of insulin resistance (mean HOMA-IR 5.5 ± 3.4) despite not meeting the diagnostic criteria for diabetes, and low-level inflammation (mean CRP 3.9 mg/l ± 3.8 mg/l). One hundred and 95 participants (83%) completed the program resulting in a significant reduction in BMI-SDS, HOMA-IR, CRP, and leptin and a significant increase in adiponectin (mean change compared to baseline -0.14, -0.85, -1.0 mg/l, -2.8 ng/ml, and 0.5 μg/ml, respectively; p < 0.001 each). Effects on BMI-SDS, HOMA-IR, CRP, and adiponectin were largely independent whereas leptin was positively correlated with BMI-SDS and total fat mass before and after intervention (r = 0.56 and 0.61, p < 0.001 each). Short-term multidisciplinary intervention successfully improved body composition, insulin sensitivity, low-level systemic inflammation, and the adipokine profile in childhood obesity. Our findings highlight the immediate connection between obesity and the pathophysiology of its sequelae, and emphasize the importance of early intervention. Continued lifestyle modification is likely necessary to consolidate and augment the long-term effects.

Assessment of Iron Metabolism-Related Parameters in Obese Children

Objectives: The aim of the study was to assess the possible associations among biochemical parameters that may be correlated with the possible mechanisms of iron metabolism in healthy children with normal body mass index (BMI), along with morbid obese (MO) children with and without metabolic syndrome (MetS). Methods: To this end, children aged 6-18 years with no history of any acute or chronic diseases were selected as the population of this prospective case-control study. Thirty MO children (with BMI higher than 99th percentile and without MetS findings), 28 MO children (with BMI higher than 99th percentile and with MetS), and 30 healthy children (with BMI values between 15th and 85th percentiles) participated in the study. Then, anthropometric measurements were recorded, followed by performing the complete blood count and serum iron profile. In addition, ferritin, transferrin, hepcidin, irisin, ferroportin, brain-derived neurotrophic factor (BDNF), WISP1, and PTP1/fortilin levels were measured using ELISA. Finally, statistical analyses were performed and P<0.05 was considered as the level of statistical significance. Results: Significant differences were obtained among the groups regarding anthropometric measurements, blood pressures, triacylglycerols, and high-density lipoprotein cholesterol levels. Further, there was a tendency toward an iron deficiency in both MO groups while an increase in ferritin levels was significant in the MetS group. However, BDNF, hepcidin, and ferroportin demonstrated no significant difference among the groups. Eventually, although the above-mentioned parameters were statistically insignificant, fortilin levels indicated a gradual decrease whereas irisin levels represented an increase from control group toward morbid obesity and MetS. Conclusion: In our study, obesity severity and the tendency toward iron deficiency were in accordance with each other. Particularly, different WISP-1 levels in the groups may help predict future complications, along with its use in diagnosing obesity.

A Moderate Interleukin-6 Reduction, Not a Moderate Weight Reduction, Improves the Serum Iron Status in Diet-Induced Weight Loss with Fish Oil Supplementation

BACKGROUND & AIMS

Whether moderate weight loss or a reduction in IL-6 improves the serum iron status in overweight (OW) and obese adults supplemented with or without fish oil is explored.

METHODS AND RESULTS

In total, 93 OW/obese Taiwanese adults with ≥2 metabolic components are randomized to a 12-week calorie-restricted diet with meal replacement alone (CRMR, n = 45) or supplemented with fish oil (CRMRF, n = 48). Mean reductions in the %body weight and serum IL-6 are 7.5% versus 5.9% and 21% versus 35% for the CRMR and CRMRF groups, respectively. In the CRMRF group, a moderate loss of IL-6 (reduced ≥35%) also significantly improves the serum iron and transferrin saturation compared to those with loss of <35% in the mean serum IL-6 or those of the CRMR group who has a moderate loss of IL-6 (reduced ≥21%) (all p < 0.05). In contrast, modest weight loss does not improve the serum iron status.

CONCLUSIONS

Fish oil is ineffective as an adjunct for weight or fat loss but has beneficial effects on preserving the lean body mass. A significant improvement in the iron status is only observed in those with moderate loss of serum IL-6 supplemented with fish oil.

Carnosine supplementation reduces plasma soluble transferrin receptor in healthy overweight or obese individuals: a pilot randomised trial

Abnormalities of iron homeostasis have been linked to insulin resistance, type 2 diabetes and cardiovascular disease. Carnosine, an over-the-counter food supplement with chelating properties, has been shown to decrease serum iron and improve glucose metabolism in diabetic rodents. We have previously demonstrated that carnosine supplementation prevented worsening of glucose metabolism in healthy overweight and obese middle-aged adults. Yet, the impact of carnosine on markers of iron metabolism in humans has not been investigated. We aimed to determine whether carnosine supplementation has an effect on iron parameters in overweight and obese, otherwise healthy adults. We included 26 participants, who were randomly allocated to receive 1 g carnosine (n = 14) or identical placebo (n = 12) twice daily for 12 weeks. Iron parameters including iron, ferritin, transferrin, soluble transferrin receptor, total iron binding capacity and iron saturation were measured in serum or plasma by standard commercial assays. Carnosine supplementation decreased plasma soluble transferrin receptor compared to placebo (mean change difference ± standard error: - 0.07 ± 0.03 mg/l, p = 0.04). None of the other iron parameters were different between carnosine and placebo groups. At follow-up, soluble transferrin receptor was associated inversely with urinary carnosine concentrations and positively with serum carnosinase-1 activity (both p < 0.02). Our findings suggest that carnosine may modulate iron metabolism in high-risk groups which could ameliorate insulin resistance and prevent type 2 diabetes. Larger human clinical trials are required to confirm our results.

Serum and gene expression levels of CT-1, IL-6, and TNF-α after a lifestyle intervention in obese children

BACKGROUND

Inflammation related molecules such as tumor necrosis factor-α (TNF-α), interleukin 6 (IL-6), and cardiotrophin-1 (CT-1) are highly expressed in obese individuals and could partly explain some comorbidities associated to obesity. In obese children, lifestyle interventions are able to lower inflammation and reduce cardiovascular risk factors associated with obesity. The aim of the present work was to study changes in inflammation-related molecules serum and peripheral blood mononuclear cells (PBMC) transcript levels after a 10-week lifestyle intervention in obese children and asses their potential association with glucose metabolism.

METHODS

Twenty-three obese children (mean age 11.5 years; 48% males) underwent a 10-week lifestyle not controlled intervention trial. Anthropometric and biochemical measurements were analyzed. Transcript analysis for CT-1, IL-6, and TNF-α in PBMC were performed by RT-PCR. Serum cytokine levels were also measured at baseline and after 10-weeks.

RESULTS

Participants achieved a significant reduction in body adiposity (0.34 decrease in body mass index-standard deviation), total cholesterol, and glucose levels after 10-weeks. A Significant decrease in serum TNF-α and C reactive protein (CRP) were observed. CT-1 transcript levels were significantly reduced (P = .005) after lifestyle intervention, and these changes were significantly correlated with changes in serum CT-1 levels (r = 0.451; P = .031). In multiple regression analysis baseline CT-1 transcript levels were positively associated with final insulin (R² = 0.506; P = .035) and HOMA-IR values (R² = 0.473; P = .034).

CONCLUSIONS

We reported that serum CRP, TNF-α, as well as PBMC CT-1 transcript levels were reduced after lifestyle intervention in obese children. More studies are needed to clarify the role of inflammation-related molecules in glucose metabolism.

Physical exercise intervention at school improved hepcidin, inflammation, and iron metabolism in overweight and obese children and adolescents

BackgroundObesity is often associated with iron deficiency in children and adolescents. We aimed to study the effect of an 8-month physical exercise (PE) intervention on hepcidin and other markers of inflammation and on iron status in overweight/obese children and adolescents.MethodsSeventy-three overweight/obese children and adolescents participated in the 8-month-long longitudinal study. They were divided into two groups according to their participation in an after-school PE program: the PE group (n=44) and the control group (n=29). Hepcidin, interleukin (IL)-6, C-reactive protein (CRP), iron, ferritin, transferrin, and soluble transferrin receptor (sTfR) were evaluated.ResultsAt baseline, IL-6 correlated positively with hepcidin and negatively with iron and transferrin saturation, suggesting that increasing adiposity associates with increasing IL-6 and hepcidin synthesis, reducing iron availability. After 8 months, the PE group showed a decrease in BMI z-score (P=0.003), body fat mass (P=0.012), CRP (P=0.002), IL-6 (P=0.048), ferritin (P=0.013), hepcidin (P=0.040), and sTfR (P=0.010), and an increase in iron concentration (P=0.002). Moreover, the PE group, when compared with the control group, showed lower weight (P=0.026), BMI (P=0.040), waist circumference (P=0.010), and waist-to-height ratio (P=0.046).ConclusionWe showed that an 8-month-long intervention at school allowed a reduction in BMI z-score and an improvement in inflammation, reducing hepcidin levels and the disturbances in iron status.

Systematic review and meta-analysis of school-based obesity interventions in mainland China

Background

Numerous school-based interventions for childhood obesity have been emerging in mainland China in recent decades, but little is known about the effectiveness of such interventions. This study aims to assess the effectiveness of school-based interventions for childhood obesity conducted in mainland China.

Methods

A systematic search was undertaken in eight databases to identify both randomized and non-randomized controlled trials from January 1990 to December 2015 examining the effectiveness of school-based obesity interventions. A random effects meta-analysis was conducted assessing the impact of included interventions on (body mass index) BMI. The quality of each included studies were assessed using Effective Public Health Practice Project Quality Assessment Tool. A P value <0.05 (two-sided) was considered statistically significant.

Result

Of the seventy-six included studies, we found physical activity and health education were the two most common components of interventions. More treatment studies were effective compared with prevention studies (85.0% vs. 58.3%). Comprehensive interventions involving physical activity and health education appeared more effective than the physical activity only interventions in both obesity treatment and prevention studies. The meta-analyses showed comprehensive interventions involving physical activity and health education had larger effect on the change of BMI than physical activity only interventions (treatment studies: -1.80 kg/m² (95% CI: -2.15,-1.44) vs. -0.91 kg/m² (95% CI: -1.15,-0.67); prevention studies: -0.19 kg/m² (95% CI: -0.27, -0.11) vs. +0.05 kg/m² (95% CI: -0.04, +0.15)).

Conclusions

Comprehensive school-based interventions may assist in tackling the rising prevalence of childhood obesity in mainland China.

β-Carotene Concentration and Its Association with Inflammatory Biomarkers in Spanish Schoolchildren

AIM

To examine the correlation between inflammatory biomarkers and plasma β-carotene levels in children.

METHODS

A total of 564 Spanish schoolchildren aged 9-12 were observed and studied. Plasma β-carotene levels were assessed by HPLC. A β-carotene level <4.83 µg/dL (0.09 µmol/L) was considered deficient. Plasma tumour necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were measured by immunoenzyme assays. Serum high-sensitivity C-reactive protein (hs-CRP) was tested by immunonephelometry.

RESULTS

Subjects who were β-carotene-deficient (23.1% of the studied children) had higher IL-6 levels than subjects with normal β-carotene concentrations. The log-IL-6 and log-hs-CRP concentrations, but not the log-TNF-α level, were strongly and inversely related to the plasma log-β-carotene level (taking into account log-age, energy intake, log-triglycerides, gender, log-body mass index, log-β-carotene intake, energy from lipids and cholesterol as covariables). When the 3 inflammatory biomarkers were introduced into the regression model along with the corresponding covariables, only the log-IL-6 level was related to the plasma log-β-carotene level (β = -0.505 ± 0.078; p < 0.001).

CONCLUSIONS

Inflammatory status, in particular IL-6 levels, appears to be negatively associated with plasma β-carotene levels in schoolchildren.

Diet, physical activity and behavioural interventions for the treatment of overweight or obese children from the age of 6 to 11 years

BACKGROUND

Child and adolescent overweight and obesity has increased globally, and can be associated with significant short- and long-term health consequences. This is an update of a Cochrane review published first in 2003, and updated previously in 2009. However, the update has now been split into six reviews addressing different childhood obesity treatments at different ages.

OBJECTIVES

To assess the effects of diet, physical activity and behavioural interventions (behaviour-changing interventions) for the treatment of overweight or obese children aged 6 to 11 years.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, PsycINFO, CINAHL, LILACS as well as trial registers ClinicalTrials.gov and ICTRP Search Portal. We checked references of studies and systematic reviews. We did not apply any language restrictions. The date of the last search was July 2016 for all databases.

SELECTION CRITERIA

We selected randomised controlled trials (RCTs) of diet, physical activity, and behavioural interventions (behaviour-changing interventions) for treating overweight or obese children aged 6 to 11 years, with a minimum of six months' follow-up. We excluded interventions that specifically dealt with the treatment of eating disorders or type 2 diabetes, or included participants with a secondary or syndromic cause of obesity.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened references, extracted data, assessed risk of bias, and evaluated the quality of the evidence using the GRADE instrument. We contacted study authors for additional information. We carried out meta-analyses according to the statistical guidelines in the Cochrane Handbook for Systematic Reviews of Interventions.

MAIN RESULTS

We included 70 RCTs with a total of 8461 participants randomised to either the intervention or control groups. The number of participants per trial ranged from 16 to 686. Fifty-five trials compared a behaviour-changing intervention with no treatment/usual care control and 15 evaluated the effectiveness of adding an additional component to a behaviour-changing intervention. Sixty-four trials were parallel RCTs, and four were cluster RCTs. Sixty-four trials were multicomponent, two were diet only and four were physical activity only interventions. Ten trials had more than two arms. The overall quality of the evidence was low or very low and 62 trials had a high risk of bias for at least one criterion. Total duration of trials ranged from six months to three years. The median age of participants was 10 years old and the median BMI z score was 2.2.Primary analyses demonstrated that behaviour-changing interventions compared to no treatment/usual care control at longest follow-up reduced BMI, BMI z score and weight. Mean difference (MD) in BMI was -0.53 kg/m2 (95% confidence interval (CI) -0.82 to -0.24); P < 0.00001; 24 trials; 2785 participants; low-quality evidence. MD in BMI z score was -0.06 units (95% CI -0.10 to -0.02); P = 0.001; 37 trials; 4019 participants; low-quality evidence and MD in weight was -1.45 kg (95% CI -1.88 to -1.02); P < 0.00001; 17 trials; 1774 participants; low-quality evidence.Thirty-one trials reported on serious adverse events, with 29 trials reporting zero occurrences RR 0.57 (95% CI 0.17 to 1.93); P = 0.37; 4/2105 participants in the behaviour-changing intervention groups compared with 7/1991 participants in the comparator groups). Few trials reported health-related quality of life or behaviour change outcomes, and none of the analyses demonstrated a substantial difference in these outcomes between intervention and control. In two trials reporting on minutes per day of TV viewing, a small reduction of 6.6 minutes per day (95% CI -12.88 to -0.31), P = 0.04; 2 trials; 55 participants) was found in favour of the intervention. No trials reported on all-cause mortality, morbidity or socioeconomic effects, and few trials reported on participant views; none of which could be meta-analysed.As the meta-analyses revealed substantial heterogeneity, we conducted subgroup analyses to examine the impact of type of comparator, type of intervention, risk of attrition bias, setting, duration of post-intervention follow-up period, parental involvement and baseline BMI z score. No subgroup effects were shown for any of the subgroups on any of the outcomes. Some data indicated that a reduction in BMI immediately post-intervention was no longer evident at follow-up at less than six months, which has to be investigated in further trials.

AUTHORS' CONCLUSIONS

Multi-component behaviour-changing interventions that incorporate diet, physical activity and behaviour change may be beneficial in achieving small, short-term reductions in BMI, BMI z score and weight in children aged 6 to 11 years. The evidence suggests a very low occurrence of adverse events. The quality of the evidence was low or very low. The heterogeneity observed across all outcomes was not explained by subgrouping. Further research is required of behaviour-changing interventions in lower income countries and in children from different ethnic groups; also on the impact of behaviour-changing interventions on health-related quality of life and comorbidities. The sustainability of reduction in BMI/BMI z score and weight is a key consideration and there is a need for longer-term follow-up and further research on the most appropriate forms of post-intervention maintenance in order to ensure intervention benefits are sustained over the longer term.

Acupuncture Improves Intestinal Absorption of Iron in Iron-deficient Obese Patients: A Randomized Controlled Preliminary Trial

Background:

Obesity has an adverse effect on iron status. Hepcidin-mediated inhibition of iron absorption in the duodenum is a potential mechanism. Iron-deficient obese patients have diminished response to oral iron therapy. This study was designed to assess whether acupuncture could promote the efficacy of oral iron supplementation for the treatment of obesity-related iron deficiency (ID).

Methods:

Sixty ID or ID anemia (IDA) patients with obesity were screened at Beijing Hospital of Traditional Chinese Medicine and were randomly allocated to receive either oral iron replacement allied with acupuncture weight loss treatment (acupuncture group, n = 30) or oral iron combined with sham-acupuncture treatment (control group, n = 30). Anthropometric parameters were measured and blood samples were tested pre- and post-treatment. Differences in the treatment outcomes of ID/IDA were compared between the two groups.

Results:

After 8 weeks of acupuncture treatment, there was a significant decrease in body weight, body mass index, waist circumference, and waist/hip circumference ratio of patients in the acupuncture group, while no significant changes were observed in the control group. Oral iron supplementation brought more obvious improvements of iron status indicators including absolute increases in serum iron (11.08 ± 2.19 μmol/L vs. 4.43 ± 0.47 μmol/L), transferrin saturation (11.26 ± 1.65% vs. 1.01 ± 0.23%), and hemoglobin (31.47 ± 1.19 g/L vs. 21.00 ± 2.69 g/L) in the acupuncture group than control group (all P < 0.05). Meanwhile, serum leptin (2.26 ± 0.45 ng/ml vs. 8.13 ± 0.55 ng/ml, P < 0.05) and hepcidin (3.52 ± 1.23 ng/ml vs. 6.77 ± 0.84 ng/ml, P < 0.05) concentrations declined significantly in the acupuncture group than those in the control group.

Conclusion:

Acupuncture-based weight loss can enhance the therapeutic effects of iron replacement therapy for obesity-related ID/IDA through improving intestinal iron absorption, probably by downregulating the systemic leptin-hepcidin levels.

Interrelations among the adipocytokines leptin and adiponectin, oxidative stress and aseptic inflammation markers in pre- and early-pubertal normal-weight and obese boys

PURPOSE

Presumed interrelationships among deleterious aspects of adipose tissue metabolism, inflammation, and cellular oxidative stress could be influenced by pubertal hormonal changes. They were investigated in pre- and early pubertal normal-weight and obese boys before and after an exercise bout employed as an energy demanding stimulator.

METHODS

Cross-sectional study. Seventy-six healthy pre- (mean ± SD, 10.6 ± 0.2 years old, 28 normal-weight, and 11 obese) and early-(11.4 ± 0.2 years old, 25 normal-weight, and 12 obese) pubertal boys, were blood-sampled before and after a bout of exercise at 70% VO₂ max. Leptin, adiponectin, markers of inflammation (high-sensitivity C-reactive protein, high sensitivity IL-6), pro- (thiobarbitouric acid reactive substances, protein carbonyls) and anti- (glutathione, oxidized glutathione, glutathione peroxidase, catalase, total antioxidant capacity) oxidation were measured.

RESULTS

Baseline and post-exercise adiponectin was greater and leptin and high-sensitivity C-reactive protein were lower in normal-weight than in obese pre- and early pubertal boys, while high sensitivity IL-6 was greater in obese than in normal-weight pre-pubertal boys. In pre-pubertal obese boys: at baseline, high-sensitivity C-reactive protein correlated negatively with catalase; high sensitivity IL-6 correlated positively with protein carbonyls; Δ (difference during exercise) adiponectin correlated positively with Δcatalase. In all boys: at baseline, high sensitivity IL-6 correlated positively with leptin and was the best negative and the second best positive predictor for post-exercise glutathione/oxidized glutathione and protein carbonyls, respectively; leptin was the best negative predictor for post-exercise glutathione; waist to height ratio was the best positive predictor for post-exercise thiobarbitouric acid reactive substances; body mass index z-score and adiponectin were, respectively, the best positive predictor for post-exercise protein carbonyls and catalase.

CONCLUSIONS

In all subjects, leptin and adiponectin predict negatively and positively anti-oxidation, respectively, while high sensitivity IL-6 predicts positively and negatively pro- and anti-oxidation, respectively. High-sensitivity C-reactive protein is increased and negatively associated with anti-oxidation in pre-pubertal obese boys, suggesting that childhood obesity is associated with aseptic inflammation and oxidative stress.

The initiation of metabolic inflammation in childhood obesity

An understanding of the events that initiate metabolic inflammation (metainflammation) can support the identification of targets for preventing metabolic disease and its negative effects on health. There is ample evidence demonstrating that the initiating events in obesity-induced inflammation start early in childhood. This has significant implications on our understanding of how early life events in childhood influence adult disease. In this Review we frame the initiating events of metainflammation in the context of child development and discuss what this reveals about the mechanisms by which this unique form of chronic inflammation is initiated and sustained into adulthood.

Multicomponent Lifestyle Interventions for Treating Overweight and Obesity in Children and Adolescents: A Systematic Review and Meta-Analyses

BACKGROUND

Treatment of childhood obesity is important in preventing development of obesity-related diseases later in life. This systematic review evaluates the effect of multicomponent lifestyle interventions for children and adolescents from 2 to 18 years.

METHODS AND RESULTS

We performed systematic searches in nine databases. Thirty-nine studies met the criteria for meta-analyses. We found a significant difference in body mass index (BMI) after 6 months (MD -0.99 (95% CI -1.36 to -0.61)), 12 months (MD -0.67 (95% CI -1.01 to -0.32)), and 24 months (MD -0.96 (95% CI -1.63 to -0.29)) in favour of multicomponent lifestyle interventions compared to standard, minimal, and no treatment. We also found a significant difference in BMI Z scores after 6 months (MD -0.12 (95% CI -0.17 to -0.06)), 12 months (MD -0.16 (95% CI -0.21 to -0.11)), and 24 months (MD -0.16 (95% CI -0.21 to -0.10)) in favour of multicomponent lifestyle interventions. Subgroup analyses suggested an increased effect in specialist health care with a group treatment component included in the intervention.

CONCLUSION

Multicomponent lifestyle interventions have a moderate effect on change in BMI and BMI Z score after 6, 12, and 24 months compared with standard, minimal, and no treatment.

Inflammatory, endocrine and metabolic correlates of fatigue in obese children

Alterations in endocrine functions and low-grade systemic inflammation represent fundamental characteristics of obesity. These biological systems have been repeatedly linked to fatigue symptoms. The aim of the study was to assess the relationship between fatigue dimensions and metabolic/inflammatory markers in a sample of non-diabetic obese children. The possibility that inflammation-induced alterations in tryptophan metabolism relates to specific dimensions of fatigue was also investigated in a subsample of patients. The study was conducted in 41 obese children, median aged 12 [9-15] years, recruited in a pediatric tertiary center. Three dimensions of fatigue (e.g., general fatigue, sleep/rest, cognitive fatigue) were assessed using the Pediatric Quality of Life Inventory Multidimentional Fatigue Scale. In addition, a principal component analysis was performed to identify fatigue dimensions that were specific to the population under study. This analysis extracted five relevant dimensions corresponding respectively to concentration, energy, self-perceived cognitive efficiency, sleep/rest and motivation/anhedonia. Blood samples were collected for the measurement of inflammatory and metabolic markers, including high sensitivity C-reactive protein (hs-CRP), insulin, uricemia and glycaemia. Tryptophan, kynurenine and neopterin levels were also determined in a subsample of 17 patients. In the whole population under study, cognitive fatigue and reduced motivation/anhedonia were associated with BMI, independently of sex and age. The dimension of reduced motivation/anhedonia was associated with insulin resistance and inflammatory biomarkers. The association with insulin resistance persisted when the extent of fat mass (BMI-SDS) was taken into account. No association was found between tryptophan metabolism and specific dimensions of fatigue, but kynurenine and the kynurenine/tryptophan ratio correlated with insulin and HOMA-IR. These data indicate that insulin resistance in non diabetic obese children is associated with both cognitive fatigue and reduced motivation/anhedonia and with alterations in tryptophan metabolism. Further investigations are needed to determine whether inflammation-induced alterations in tryptophan metabolism is directly or indirectly implicated in insulin resistance and related fatigue.

Asthma as a disruption in iron homeostasis

Over several decades, asthma has evolved from being recognized as a single disease to include a diverse group of phenotypes with dissimilar natural histories, pathophysiologies, responses to treatment, and distinctive molecular pathways. With the application of Occam's razor to asthma, it is proposed that there is one cause underlying the numerous phenotypes of this disease and that the responsible molecular pathway is a deficiency of iron in the lung tissues. This deficiency can be either absolute (e.g. asthma in the neonate and during both pregnancy and menstruation) or functional (e.g. asthma associated with infections, smoking, and obesity). Comparable associations between asthma co-morbidity (e.g. eczema, urticaria, restless leg syndrome, and pulmonary hypertension) with iron deficiency support such a shared mechanistic pathway. Therapies directed at asthma demonstrate a capacity to impact iron homeostasis, further strengthening the relationship. Finally, pathophysiologic events producing asthma, including inflammation, increases in Th2 cells, and muscle contraction, can correlate with iron availability. Recognition of a potential association between asthma and an absolute and/or functional iron deficiency suggests specific therapeutic interventions including inhaled iron.

Effect of Spirulina maxima Supplementation on Calcium, Magnesium, Iron, and Zinc Status in Obese Patients with Treated Hypertension

The effects of Spirulina maxima supplementation on calcium, magnesium, iron, and zinc status were studied in a double-blind placebo-controlled trial of 50 obese subjects with treated hypertension, each randomized to receive 2 g of spirulina or a placebo daily for 3 months. At baseline and after treatment, the calcium, magnesium, iron, and zinc concentration in plasma was assessed. It was found that 3 months of S. maxima supplementation resulted in a significant decrease in the iron level in the plasma of obese patients. In conclusion, this is the first clinical study on the influence of spirulina supplementation on mineral status in obese patients with hypertension. Spirulina supplementation affects the iron status of obese Caucasians with well-treated hypertension.

Is there a mismatch between who gets iron supplementation and who needs it? A cross-sectional study of iron supplements, iron deficiency anaemia and socio-economic status in Australia

Fe deficiency anaemia (IDA) is more prevalent in lower socio-economic groups; however, little is known about who actually receives Fe supplements. This paper aims to determine whether the groups most likely to have IDA are the most likely to be taking Fe supplements. Logistic regression analysis was conducted using the cross-sectional, nationally representative National Nutrition and Physical Activity Survey and National Health Measures Survey. After adjusting for other factors, those whose main language spoken at home was not English had twice the odds of having IDA compared with those whose main language spoken at home was English (95% CI 1·00, 4·32). Those who were not in the labour force also had twice the odds of having IDA as those who were employed (95% CI 1·16, 3·41). Those in income quintile 1 had 3·7 times the odds of having IDA compared with those in income quintile 5 (95% CI 1·42, 9·63). Those whose main language spoken at home was not English were significantly less likely to take Fe supplements (P=0·002) than those whose main language spoken at home was English. There was no significant difference in the likelihood of taking Fe supplements between those who were not in the labour force and those who were employed (P=0·618); between those who were in income quintile 1 and in higher income quintiles; and between males and females (P=0·854), after adjusting for other factors. There is a mismatch between those who are most in need of Fe supplements and those who currently receive them.

A review of iron studies in overweight and obese children and adolescents: a double burden in the young?

INTRODUCTION

The connection between iron and excessive adiposity has received much research interest. Although children and adolescents have unique developmental phases and nutritional demands, to date, reviews of iron in the overweight (OW) and obese (OB) have combined studies of children and adults or have focussed on adults.

PURPOSE

The aim of this review was to critically evaluate studies of the relationship between iron and OW and obesity in children and adolescents, with emphasis on iron status, oral iron response, dietary intake and systemic inflammatory markers.

METHODS

A PubMed search was conducted to identify relevant articles published up to December 2015. Combinations of the following keywords were used: iron, OW, OB, children, adolescents, diet, hepcidin, inflammation, fortification, supplementation, weight loss, trace elements, obesity, iron deficiency (ID), minerals.

RESULTS AND CONCLUSION

A higher prevalence of ID, or risk of ID, among OW and OB children and adolescents has been consistently observed. Chronic inflammation caused by excessive adiposity offers a plausible explanation for this finding, rather than dietary factors. However, future studies must employ screening for the presence of both acute and chronic infections and inflammatory conditions and report other factors such as pubertal status. Intervention studies, although few, indicate that OW and OB children and adolescents have reduced response to oral iron. Further trials are needed to explore the connection between body fat mass, inflammatory proteins and iron absorption, together with the effect of weight loss on iron status in iron-deficient OW and OB children and adolescents.

Iron Metabolism Dysregulation and Cognitive Dysfunction in Pediatric Obesity: Is There a Connection?

Obesity and iron deficiency (ID) are two of the most common nutritional disorders in the world. In children both conditions deserve particular attention. Several studies revealed an association between obesity and iron deficiency in children and, in some cases, a reduced response to oral supplementation. The connecting mechanism, however, is not completely known. This review is focused on: (1) iron deficiency in obese children and the role of hepcidin in the connection between body fat and poor iron status; (2) iron status and consequences on health, in particular on cognitive function; (3) cognitive function and obesity; (4) suggestion of a possible link between cognitive dysfunction and ID in pediatric obesity; and implications for therapy and future research.

The whole body cryostimulation modifies irisin concentration and reduces inflammation in middle aged, obese men

The anti-inflammatory effect induced by exposure to low temperature might trigger the endocrine function of muscle and fat tissue. Thus, the aim of this study was to investigate the influence of the whole body cryostimulation (CRY) on irisin, a myokine which activates oxygen consumption in fat cells as well as thermogenesis. In addition, the relationship between hepcidin (Hpc) - hormone regulating iron metabolism, and inflammation was studied. A group of middle aged men (n = 12, 38 ± 9 years old, BMI > 30 kg m(-2)) participated in the study. Subjects were exposed to a series of 10 sessions in a cryogenic chamber (once a day at 9:30 am, for 3 min, at temperature -110 °C). Blood samples were collected before the first cryostimulation and after completing the last one. Prior to treatment body composition and fitness level were determined. The applied protocol of cryostimulation lead to rise the blood irisin in obese non-active men (338.8 ± 42.2 vs 407.6 ± 118.5 ng mL(-1)), whereas has no effect in obese active men (371.5 ± 30.0 vs 343.3 ± 47.6 ng mL(-1)). Values recorded 24 h after the last cryo-session correlated significantly with the fat tissue, yet inversely with the skeletal muscle mass. Therefore, we concluded the subcutaneous fat tissue to be the main source of irisin in response to cold exposures. The applied cold treatment reduced the high sensitivity C-reactive protein (hsCRP) and Hpc concentration confirming its anti-inflammatory effect.

The Potential Role of Iron and Copper in Pediatric Obesity and Nonalcoholic Fatty Liver Disease

Obesity is a rapidly growing health problem and is paralleled by a multitude of comorbidities, including nonalcoholic fatty liver disease (NAFLD). NAFLD has become the most common chronic liver disease in both adults and children. The current understanding of NAFLD is still fragmentary. While simple steatosis is characterized by the interplay between excessive free fatty acid accumulation and hepatic insulin resistance, the progression to NASH has been related to oxidative stress and a proinflammatory state with dysbalanced adipokine, cytokine levels, and endotoxin-mediated immune response. In addition, oxidative stress has been suggested to play a central role for the sequelae leading to NASH. Trace elements are critical in regulatory, immunologic, and antioxidant functions resulting in protection against inflammation and peroxidation and consequently against the known comorbidities of obesity. Disruptions of the metal detoxification processes located in the liver are plausibly related to NAFLD development via oxidative stress. Perturbations of iron and copper (Cu) homeostasis have been shown to contribute to the pathogenesis of NAFLD. This review presents current data from pediatric studies. In addition, data from adult studies are summarized where clinical relevance may be extrapolated to pediatric obesity and NAFLD.

Effect of regular circus physical exercises on lymphocytes in overweight children

Obesity associated with a sedentary lifestyle can lead to changes in the immune system balance resulting in the development of inflammatory diseases. The aim of this study was to compare lymphocyte activation mechanisms between overweight children practicing regular circus physical exercises with non-exercised children. The study comprised 60 pubescent children randomly divided into 4 groups: Overweight Children (OWC) (10.67 ± 0.22 years old), Overweight Exercised Children (OWE) (10.00 ± 0.41 years old), Eutrophic Children (EC) (11.00 ± 0.29 years old) and Eutrophic Exercised Children (EE) (10.60 ± 0.29 years old). OWE and EE groups practiced circus activities twice a week, for 4.3 ± 0.5 and 4.4 ± 0.5 months, respectively. Percentage of T regulatory cells (Treg) and the expression of CD95 and CD25 in CD4+ lymphocytes were evaluated by flow cytometry. Lymphocyte proliferation capacity was measured by [14C]-thymidine incorporation and mRNA expression of IL-35, TGF-beta, IL-2 and IL-10 by real-time PCR. Lymphocyte proliferation was higher in OWC and OWE groups compared with the EC (3509 ± 887; 2694 ± 560, and 1768 ± 208 cpm, respectively) and EE (2313 ± 111 cpm) groups. CD95 expression on lymphocytes was augmented in the EC (953.9 ± 101.2) and EE groups (736.7 ± 194.6) compared with the OWC (522.1 ± 125.2) and OWE groups (551.6 ± 144.5). CTLA-4 expression was also lower in the OWC and OWE groups compared with the EC and EE groups. Percentage of Treg, IL-35, and IL-10 mRNA expression were lower in the OWC and OWE groups compared with the EC and EE groups. In conclusion, overweight children present altered immune system balance characterized by elevated lymphocyte proliferation due to a decrease in T regulatory cell percentage. These effects were partially reverted by moderate physical exercise, as demonstrated by decreased lymphocyte proliferation.

Obesity as an emerging risk factor for iron deficiency

Iron homeostasis is affected by obesity and obesity-related insulin resistance in a many-facetted fashion. On one hand, iron deficiency and anemia are frequent findings in subjects with progressed stages of obesity. This phenomenon has been well studied in obese adolescents, women and subjects undergoing bariatric surgery. On the other hand, hyperferritinemia with normal or mildly elevated transferrin saturation is observed in approximately one-third of patients with metabolic syndrome (MetS) or nonalcoholic fatty liver disease (NAFLD). This constellation has been named the “dysmetabolic iron overload syndrome (DIOS)”. Both elevated body iron stores and iron deficiency are detrimental to health and to the course of obesity-related conditions. Iron deficiency and anemia may impair mitochondrial and cellular energy homeostasis and further increase inactivity and fatigue of obese subjects. Obesity-associated inflammation is tightly linked to iron deficiency and involves impaired duodenal iron absorption associated with low expression of duodenal ferroportin (FPN) along with elevated hepcidin concentrations. This review summarizes the current understanding of the dysregulation of iron homeostasis in obesity.