Serum leptin levels in childhood celiac disease

Serum Concentrations of Insulin, Ghrelin, Adiponectin, Leptin, Leptin Receptor and Lipocalin-2 in Children with Celiac Disease Who Do and Do Not Adhere to a Gluten-Free Diet

Background/Aims

The roles of the many bioactive peptides in the pathogenesis of celiac disease remain unclear. To evaluate the serum concentrations of insulin, ghrelin, adiponectin, leptin, leptin receptor, and lipocalin-2 in children with celiac disease who do and do not adhere to a gluten-free diet (GFD, intermittent adherence).

Methods

Prepubertal, pubertal, and adolescent celiac children were included in this study (74 girls and 53 boys on a GFD and 80 girls and 40 boys off of a GFD).

Results

Insulin levels in prepubertal (9.01±4.43 μIU/mL), pubertal (10.3±3.62 μIU/mL), and adolescent (10.8±4.73 μIU/mL) girls were higher than those in boys (5.88±2.02, 8.81±2.88, and 8.81±2.26 μIU/mL, respectively) and were neither age-dependent nor influenced by a GFD. Prepubertal children off of a GFD exhibited higher ghrelin levels than prepubertal children on a GFD. Adiponectin levels were not age-, sex- nor GFD-dependent. Adherence to a GFD had no effect on the expression of leptin, leptin receptor, and lipocalin-2.

Conclusions

Adherence to a GFD had no influence on the adiponectin, leptin, leptin receptor, and lipocalin-2 concentrations in celiac children, but a GFD decreased highly elevated ghrelin levels in prepubertal children. Further studies are required to determine whether increased insulin concentrations in girls with celiac disease is suggestive of an increased risk for hyperinsulinemia.

Incretins, amylin and other gut-brain axis hormones in children with coeliac disease

BACKGROUND

Previous research indicated that coeliac disease (CD) is associated with type 1 diabetes mellitus (T1DM). However, the gut-brain axis peptide hormones secretion has not been evaluated so far in patients with CD prior to treatment initiation or under treatment, irrespective of patients having concomitant T1DM or not. The aim of the study was therefore to evaluate these gut hormones at the preprandial levels of patients with CD before and under treatment.

METHODS

Of forty-seven CD children, 12 untreated (UCD), 22 treated with gluten-free diet (TCD) and 13 treated CD with coexisting T1DM (DCD), and 18 healthy controls (HC) were enrolled. Preprandial glucagon-like-peptide-1 (GLP-1), glucose-dependent-insulinotropic-polypeptide (GIP), active amylin, acylated ghrelin (AG), leptin, pancreatic polypeptide (PP) and peptide-tyrosine-tyrosine (PYY) were determined with hormone-map-array technology.

RESULTS

We found in patients with CD compared with HC that the concentration of (i) GLP-1 was reduced remarkably in all patients with CD (P = 0.008), (ii) GIP was lower in patients with UCD (P = 0.008), (iii) amylin was remarkably reduced (P < 0.01) in all patients with CD, (iv) AG was significantly decreased in patients with DCD (P < 0.01), while (v) leptin, PP and PYY were not significantly different. GIP, GLP-1 and amylin levels correlated positively with insulin concentrations (P < 0.001, P = 0.004 and P < 0.01, respectively) in all patients. Amylin and GIP levels were strongly associated with triglycerides concentrations (P < 0.001, for both peptides) in children with CD.

CONCLUSIONS

Our study revealed a different secretion pattern of gut-brain axis hormones in children with CD compared with HC. The alterations in the axis were more pronounced in children with both CD and T1DM.

Adipokine profile in celiac patients: differences in comparison with patients suffering from diarrhea-predominant IBS and healthy subjects

OBJECTIVE. The role of adipokines such as resistin, leptin, and adiponectin could be pivotal in the molecular crosstalk between the inflamed intestine and the surrounding mesenteric adipose tissue. Our aims were to a) evaluate their circulating concentrations in patients with active celiac disease (ACD) and compare them to those in patients with diarrhea-predominant irritable bowel syndrome (IBS-d) and healthy subjects; b) establish the impact of genetic variability in resistin; and c) evaluate whether a 1-year gluten-free diet (GFD) modifies circulating concentrations of resistin, leptin, and adiponectin in celiac patients. MATERIAL AND METHODS. The study included 34 ACD patients, 29 IBS-d patients, and 27 healthy controls. Circulating concentrations of resistin, leptin, adiponectin, IL-6, and IL-8 were evaluated at the time of enrollment. Resistin +299 G/A polymorphism was also analysed. In CD patients, biochemical measurements were repeated after a 1-year GFD. RESULTS. Along with higher IL-6 and IL-8 plasma levels, higher resistin and adiponectin concentrations were found in ACD and IBS-d patients compared with controls (p: 0.0351 and p: 0.0020, respectively). Resistin values proved to be predictable from a linear combination of IL-8 and +299 polymorphism. GFD affected resistin (p: 0.0009), but not leptin and adiponectin concentrations. CONCLUSIONS. Our data suggest that these adipokines are involved in modulating inflammatory processes in both CD and IBS-d patients. Alterations in the adipokine profile as well as the higher prevalence of the resistin +299 G/A SNP A allele compared to controls support the hypothesis that, at least in well-defined cases of IBS, a genetic component may also be supposed.

The relationship between adiposity and stature in prepubertal children with celiac disease

BACKGROUND AND AIM

The pathogenesis of short stature in celiac disease (CD) is unknown. Obese children are generally taller than their non-obese peers; however, the role of adiposity on stature in CD is unclear. Our aim was to determine the association between adiposity and stature in CD.

SUBJECTS AND METHODS

We compared the anthropometric characteristics of prepubertal children of ages 3-12 years, with biopsy-proven CD (n=40) and who were not on gluten-free diet, to same aged, prepubertal non-CD children (n=50). Body mass index (BMI) was calculated using the formula weight/height². Sex-adjusted midparental target height (MPTH) standard deviation score (SDS) was calculated using National Children Health Statistics data for 18-year-old adults. Data were expressed as mean ± standard deviation.

RESULTS

CD subjects had significantly lower BMI SDS than controls (0.61 ± 1.22 vs. 1.28 ± 1.60, p=0.027) but were not significantly shorter than the controls (-0.05 ± 1.21 vs. 0.21 ± 1.71, p=0.41). When the patients were subdivided into the normal-weight and overweight/obese groups, the normal-weight CD patients were of similar height as the normal-weight controls (p=0.76) but were significantly shorter than both the overweight/obese controls (p<0.001) and overweight/obese CD children (p<0.001). Interestingly, the overweight/obese CD children were significantly taller than the normal-weight controls (p=0.003). The MPTH SDS did not differ between the groups.

CONCLUSIONS

Overweight/obese prepubertal children with CD were taller than both their normal-weight CD peers and the normal-weight controls, but were of similar height as the overweight/obese control subjects.

Nutritional status of children with coeliac disease

AIMS

The main aim of this study was to assess the nutritional status of children with newly diagnosed Coeliac disease (CD)with comparison to matched controls. A further aim was to assess relationships between presentation patterns and nutrition in childhood CD.

METHODS

The nutritional status of newly diagnosed CD was assessed by anthropometry, Bioelectrical Impedance and serum leptin levels, and contrasted to age and gender matched controls.

RESULTS

Twenty-five children with CD (mean age of 8.2 +/- 4.5 years) and 25 control children (mean age 8.1 +/- 4.4.) were enrolled. Thirteen (52%) children with CD had gastrointestinal symptoms with 14 having a family history of CD. At presentation 8.7% were wasted, 4.2% were stunted and 20.8% overweight, although none were obese. Mean height and weight for age, other nutritional parameters and serum leptin did not differ between the groups. Serum leptin correlated with BMI in both groups.

CONCLUSIONS

Children with CD more commonly present with atypical symptoms than with classical features. Variations in nutrition (under to overnutrition) may be seen at diagnosis, without relationship to the presence of symptoms. Leptin levels were not altered specifically in the setting of CD. Nutritional assessment remains important in the assessment and management of CD in children.

Human mast cells express leptin and leptin receptors

Mast cells are immune cells that produce and secrete a variety of mediators and cytokines that influence various inflammatory and immune processes. Leptin is a cytokine regulating metabolic, endocrine as well as immune functions via the leptin receptor which is expressed by many immune cells. However, there are no data about leptin receptor expression in mast cells. Immunohistochemical and immunofluorescent double stainings showed the expression of leptin and leptin receptors in mast cells in human skin and several parts of the respiratory, gastrointestinal and urogenital tract. Leptin was expressed in mast cells expressing the classification marker chymase, whereas a variable expression was observed in tryptase positive mast cells. For leptin receptors, the expression pattern was tissue dependent and not related to tryptase or chymase expression. Our results demonstrate the expression of leptin and leptin receptors on mast cells, suggesting paracrine and/or autocrine immunomodulatory effects of leptin on mast cells.

Bone in celiac disease

Chronic inflammation and malabsorption in celiac disease (CD) can cause bone metabolism alterations and bone mineral loss in children and adults. Bone status before and after gluten-free diet, epidemiology of fractures, and possible treatment options for CD-related osteoporosis are presented. Controversial aspects of this complication of CD are discussed. The relationship between bone derangements and celiac disease (CD) was recognized almost 50 years ago, but many questions are still open. We are now aware that osteoporosis is a relatively frequent atypical presentation of CD, especially in adults, and that undiagnosed CD can be the cause of osteoporosis and related fractures. Chronic inflammatory intestinal diseases, including CD, can affect bone and mineral metabolism because of alterations in both systemic and local regulatory factors. The pathogenetic processes are still controversial, but two main mechanisms seem to be involved: intestinal malabsorption and the presence of chronic inflammation. This review analyzes the published data on bone involvement in children, adolescents, and adults either before or after a gluten-free diet. Special attention is paid to the epidemiology of fractures in celiac patients, considering that fractures are a major complication of osteoporosis and an important problem in the management of a chronic disease like CD. The usefulness of screening osteoporotic patients systematically for CD is still an open question, but some rules can be given. Finally, the current treatment options for children and adults are discussed. Recommendations for future clinical research are proposed.

Circulating leptin levels and bone mineral density in children with biliary atresia

AIM

To investigate circulating leptin levels in biliary atresia (BA) patients and the association of leptin with bone mineral density (BMD) and the severity of BA.

METHODS

We have examined 50 patients with BA and 15 matched healthy controls. Serum leptin, osteocalcin and C-terminal telopeptide of type I collagen (CTX) levels were measured by sandwich enzyme-linked immunosorbent assay (ELISA). BMD of the lumbar spine was measured by dual energy X-ray absorptiometry.

RESULTS

Serum leptin levels of BA patients were lower than those of healthy controls (2.7 +/- 0.3 vs. 7.1 +/- 1.7 ng/mL, p = 0.0001). Among the BA patients, serum leptin levels were significantly lower in patients with jaundice than patients without jaundice (1.7 +/- 0.2 vs. 3.4 +/- 0.4 ng/mL, p = 0.001). BMD of BA patients was correlated (p < 0.001) with leptin levels, age and BMI (r = 0.55, r = 0.75 and r = 0.58, respectively). The serum CTX levels were significantly higher in jaundice patients compared with jaundice-free patients and the healthy controls (0.6 +/- 0.2 vs. 0.2 +/- 0.1 ng/mL, p = 0.01), whereas the serum osteocalcin levels in BA patients were not different from those in the controls.

CONCLUSION

Circulating leptin levels are correlated with BMD and the presence of jaundice in BA, suggesting that the leptin may play a physiological role in maintaining bone mass of BA patients with jaundice.