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The transcription factor nuclear factor-kappa-B (NFκB) is implicated in inflammatory responses, obesity and the metabolic syndrome, while immune cells appear to play a central role in mediating insulin resistance and can be used as a model to study inflammation and its relationship with insulin resistance. In peripheral blood mononuclear cells of overweight participants with the metabolic syndrome, we evaluated (1) the effect of diet-induced weight loss on the expression of genes involved in NFκB activation and (2) their association with insulin sensitivity. The genes studied were: TNF receptors TNFRSF1A and TNFRSF1B, and IL1R1, TLR4, TLR2, ICAM1, CCL5 and IKBKB. We analysed data from 34 overweight participants with abnormal glucose metabolism and the metabolic syndrome, who were randomised to a weight-reduction ( n = 24) or control group ( n = 10) for 33 weeks. The mRNA expression was measured using real-time PCR. Measures of insulin and glucose homeostasis were assessed by IVGTT and OGTT. In general, the genes studied were downregulated after weight loss intervention. The changes in TLR4, TLR2, CCL5 and TNFRSF1A mRNA expression were associated with an increase in insulin sensitivity index independently of the change in waist circumference ( p < 0.05). The change in IKBKB expression correlated with most of the changes in gene expression in the weight-reduction group. These results suggest that proteins encoded by CCL5, TLR2 and TLR4, and TNFRSF1A might contribute to insulin-resistant states that characterise obesity and the metabolic syndrome. Trial registration: ClinicalTrials.gov NCT 00621205 [ABSTRACT FROM AUTHOR]

Aims/hypothesis: Adiponectin is a circulating peptide derived from adipose tissue. It mediates its insulin-sensitising and anti-atherogenic effects on target tissues through two known receptors, adiponectin receptors 1 and 2 (ADIPOR1; ADIPOR2), which are encoded by the genes ADIPOR1 and ADIPOR2. Our aim was to study the association of ADIPOR1 gene variations with body size and risk of type 2 diabetes in subjects with impaired glucose tolerance, who participated in the Finnish Diabetes Prevention Study (DPS). Subjects and methods: We selected seven single nucleotide polymorphisms (SNPs) of the ADIPOR1 gene to perform association studies with anthropometrics and metabolic parameters at baseline, and with the risk of type 2 diabetes during the 3-year follow-up in the DPS study population. Both single SNP analysis and haplotype effects were studied. Results: Three out of seven markers studied (rs10920534, rs22757538 and rs1342387) were significantly associated with various body size measurements including weight, height, waist and hip circumference, sagittal diameter and body mass index. Furthermore, three markers (rs10920534, rs12045862 and rs7539542), of which two were different from those associating with body size, were linked to fasting and 2-h insulin levels, particularly in men at baseline. The haplotype analysis with five markers revealed seven major haplotypes in the DPS study population. The haplotype effects on body size measures were in line with those of single SNP analysis. However, none of the markers were associated with the risk of type 2 diabetes. Conclusions/interpretation: Our findings suggest that ADIPOR1 has a putative role in the development of body size, and that traits for central adiposity and insulin resistance may be dissociated from each other. [ABSTRACT FROM AUTHOR]