Empfehlungen zu Ernährung und Bewegung von Kleinkindern

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Gene repertoire of the anti-poly(Glu60Ala30Tyr10) (GAT) immune response: comparison of VH, V kappa, and D regions used by anti-GAT antibodies and monoclonal antibodies produced after anti-idiotypic immunization.

Eight monoclonal antibodies were selected from BALB/c mice immunized with two different monoclonal anti-idiotypic antibodies recognizing two discrete idiotopes characteristic of the anti-poly(Glu60Ala30Tyr10) (GAT) antibody response. These monoclonal antibodies were previously classified as Ab1 (anti-GAT-like) and Ab3 (anti-anti-idiotype) on the basis of expression of the public idiotypic specificity (p.GAT) studied with a xenogeneic serum, anti-GAT activity, and expression of various public idiotopes. All the heavy chain variable region (VH) sequences from Ab1 are nearly identical to the VH sequences of Ab1 anti-GAT monoclonal antibodies. The same type of results has been found with the Ab1 kappa light chain variable region (V kappa) sequences. Confirming our classification, Ab3 VH and V kappa sequences were found to be completely different from Ab1 VH and V kappa sequences. The Ab1 diversity (D) regions are different from one another and different from the D regions found on monoclonal anti-GAT antibodies but function similarly. These D regions are not simply derived from already described D genes. Finally, our results suggest that in the anti-GAT response VH and V kappa sequence are mainly responsible for idiotype expression.     

Interleukin-1 receptor antagonist is upregulated during diet-induced obesity and regulates insulin sensitivity in rodents

Aims/hypothesis The IL-1 receptor antagonist (IL-1Ra) is an anti-inflammatory cytokine known to antagonise the actions of IL-1. We have previously shown that IL-1Ra is markedly upregulated in the serum of obese patients, is correlated with BMI and insulin resistance, and is overexpressed in the white adipose tissue (WAT) of obese humans. The aim of this study was to examine the role of IL-1Ra in the regulation of glucose homeostasis in rodents. Methods We assessed the expression of genes related to IL-1 signalling in the WAT of mice fed a high-fat diet, as well as the effect of Il1rn (the gene for IL-1Ra) deletion and treatment with IL-1Ra on glucose homeostasis in rodents. Results We show that the expression of Il1rn and the gene encoding the inhibitory type II IL-1 receptor was upregulated in diet-induced obesity. The blood insulin:glucose ratio was significantly lower in Il1rn ^−/− animals, which is compatible with an increased sensitivity to insulin, reinforced by the fact that the insulin content and pancreatic islet morphology of Il1rn ^−/− animals were normal. In contrast, the administration of IL-1Ra to normal rats for 5 days led to a decrease in the whole-body glucose disposal due to a selective decrease in muscle-specific glucose uptake. Conclusions/interpretation The expression of genes encoding inhibitors of IL-1 signalling is upregulated in the WAT of mice with diet-induced obesity, and IL-1Ra reduces insulin sensitivity in rats through a muscle-specific decrease in glucose uptake. These results suggest that the markedly increased levels of IL-1Ra in human obesity might contribute to the development of insulin resistance.     

Characterization of monoclonal antibodies against prostaglandin E2: Fine specificity and neutralization of biological effects

The specificity and heterogeneity of the immune response of BALB/c mice immunized with prostaglandin E₂ (PGE₂) coupled to thyroglobulin was studied. All the animals (n = 50) responded to PGB₂, a transformation product of PGE₂. However, following repeated injections most of the animals (n = 30) were also able to respond to PGE₂. Cellular hybridizations were performed and five anti-PGE₂ monoclonal antibodies were isolated and analysed. They are mainly directed against the ring and the ω-chain of PGE₂ but their specificity toward the α-chain is more limited. The association constants are greater than to 1 × 10⁹M^?1. The monoclonal antibody 8E.57.71 (K_a = 1.3 × 10¹⁰M^?1) is particularly convenient for sensitive radioimmunoassays (detection limit 25pg/ml, when iodinated tracer is used). Anti-PGE₂ monoclonal antibodies were found to neutralize the specific binding of [³H]PGE₂ to rat brain hypothalamic receptors and to inhibit the PGE₂ induction of rat fundus muscular contraction.     

Prenatal exposure to ethanol: a specific effect on the H19 gene in sperm

Alcohol exposure during pregnancy induces a range of disorders in the offspring. Methylation changes in imprinted genes may play a role in the teratogenic effects of alcohol. We evaluated the possible effects of alcohol administration in pregnant mice on the methylation pattern of 5 imprinted genes (H19, Gtl2, Peg1, Snrpn and Peg3) in somatic and sperm cell DNAs of the male offspring. The effects observed were a 3% (p < 0.005) decrease in the number of methylated CpGs of H19 in the F1 offspring sperm, a 4% (p < 0.005) decrease in the number of methylated CpGs of H19 in the F2 offspring brain and a 26% (p < 0.05) decrease in the mean sperm concentration. CpGs 1 and 2 of the H19 CTCF-binding site 2 exhibited significant methylation percentage losses. H19 CTCF-binding sites are important for the regulation of Igf2 gene expression. The hypomethylation of H19 may contribute to the decreased spermatogenesis in the offspring.     

Adipose tissue is a major source of interleukin-1 receptor antagonist: upregulation in obesity and inflammation

The secreted form of the interleukin-1 receptor antagonist (IL-1Ra) is an acute-phase protein intervening in the counterregulation of inflammatory processes. We previously showed that this cytokine antagonist is upregulated in the serum of obese patients, correlating with BMI and insulin resistance. In this study, we examined the expression pattern of IL-1Ra and showed that it is highly expressed not only in liver and spleen, but also in white adipose tissue (WAT), where it is upregulated in obesity. In WAT of obese humans, IL-1Ra was also markedly increased. Moreover, human WAT explants secreted IL-1Ra into the medium, a process that could be stimulated fivefold by interferon-beta. Finally, lipopolysaccharide administration induced a long-lasting expression of IL-1Ra in mouse WAT, suggesting that adipose tissue is an important source of IL-1Ra in both obesity and inflammation. In summary, we demonstrated that WAT is one of the most important sources of IL-1Ra quantitatively, suggesting that this tissue could represent a novel target for anti-inflammatory treatment. Moreover, it can be speculated that IL-1Ra, whose production is markedly increased in WAT in obese individuals, contributes further to weight gain because of its endocrine and paracrine effects on the hypothalamus and adipocytes, respectively.     

Helicobacter pylori eradication does not cause reflux oesophagitis in functional dyspeptic patients: a randomized, investigator-blinded, placebo-controlled trial

BACKGROUND: The protective role of Helicobacter pylori in gastro-oesophageal reflux disease has been widely discussed. AIM: To assess the risk of reflux oesophagitis in patients with functional dyspepsia after treatment for H. pylori infection. METHODS: A randomized, placebo-controlled, investigator-blinded trial was carried out on 157 functional dyspeptic patients. Patients were randomized to receive lansoprazole, amoxicillin and clarithromycin (antibiotic group) or lansoprazole and identical antibiotic placebos (control group). Upper gastrointestinal endoscopy was performed at baseline, 3 and 12 months after randomization. The primary aim was to detect the presence of reflux oesophagitis. Analyses were performed on an intention-to-treat basis. RESULTS: A total of 147 patients (94%) and 133 (85%) completed 3 months and 12 months follow-up, respectively. The eradication rate of H. pylori was 90% in the antibiotic group (74 of 82) and 1% (one of 75) in the control group. At 3 months, reflux oesophagitis was diagnosed in 3.7% (three of 82) in the antibiotic group and 4% (three of 75) in the control group (P > 0.2). At 12 months, diagnosis was established in five new cases within the first group and in four within the second (P > 0.2). No difference was found in heartburn symptoms. CONCLUSIONS: H. pylori eradication does not cause reflux oesophagitis in this western population of functional dyspeptic patients.     

Mice generated by in vitro fertilization exhibit vascular dysfunction and shortened life span

Children conceived by assisted reproductive technologies (ART) display a level of vascular dysfunction similar to that seen in children of mothers with preeclamspia. The long-term consequences of ART-associated vascular disorders are unknown and difficult to investigate in healthy children. Here, we found that vasculature from mice generated by ART display endothelial dysfunction and increased stiffness, which translated into arterial hypertension in vivo. Progeny of male ART mice also exhibited vascular dysfunction, suggesting underlying epigenetic modifications. ART mice had altered methylation at the promoter of the gene encoding eNOS in the aorta, which correlated with decreased vascular eNOS expression and NO synthesis. Administration of a deacetylase inhibitor to ART mice normalized vascular gene methylation and function and resulted in progeny without vascular dysfunction. The induction of ART-associated vascular and epigenetic alterations appeared to be related to the embryo environment; these alterations were possibly facilitated by the hormonally stimulated ovulation accompanying ART. Finally, ART mice challenged with a high-fat diet had roughly a 25% shorter life span compared with control animals. This study highlights the potential of ART to induce vascular dysfunction and shorten life span and suggests that epigenetic alterations contribute to these problems.     

Immune response against poly(Glu60,Ala30,Tyr10) (GAT): immunization with monoclonal anti-idiotypic antibodies leads to the predominant stimulation of idiotypically similar immunoglobulins with anti-GAT activity

Two monoclonal anti-idiotypic antibodies (HP-Id20 and HP-Id22) recognizing two different public idiotopes expressed in the anti-poly(Glu60,Ala30,Tyr10) (GAT) response were used to immunize BALB/c and C57BL/6 mice. From these animals hybridomas were isolated. From BALB/c and C57BL/6 mice eight and seven monoclonal antibodies were characterized, respectively. The reagents were classified according to the expression of the public idiotypic specificity p.GAT (recognized by a rabbit antiserum). The anti-GAT activity and the expression of the various idiotopes characterized on anti-GAT polyclonal and monoclonal antibodies were also studied. Most of the reagents are Ab1'-type of antibody resembling anti-GAT antibodies. One anti-anti-idiotypic monoclonal antibody (Ab3) was also isolated from BALB/c mice. This suggests that in this experimental model the repertoire induced after HP-Id immunization and antigen stimulation is comparable. The idiotypic analysis of a large number of anti-GAT and of Ab1' monoclonal antibodies suggests that only two public idiotopes are involved in the anti-GAT response.