Fructosamine 3-kinase and glyoxalase I polymorphisms and their association with soluble RAGE and adhesion molecules in diabetes

Advanced glycation end-products (AGEs) are key players in pathogenesis of long-term vascular diabetes complications. Several enzymes such as fructosamine 3-kinase (FN3K) and glyoxalase I (GLO I) are crucial in preventing glycation processes. The aim of our study was to evaluate an association of FN3K (rs1056534, rs3848403) and GLO1 rs4746 polymorphisms with parameters of endothelial dysfunction and soluble receptor for AGEs (sRAGE) in 595 diabetic and non-diabetic subjects. Genotypic and allelic frequencies of mentioned polymorphisms did not differ between subgroups. In diabetic patients significant differences were observed in sRAGE concentrations according to their rs1056534 and rs3848403 genotype. While GG and CG genotypes of rs1056534 with mutated G allele were associated with significant decrease of sRAGE (GG: 1055+/-458 and CG: 983+/-363 vs. CC: 1796+/-987 ng/l, p<0.0001), in rs3848403 polymorphism TT genotype with mutated T allele was related with significant sRAGE increase (TT: 1365+/-852 vs. CT: 1016+/-401 and CC: 1087+/-508 ng/l, p=0.05). Significant differences in adhesion molecules were observed in genotype subgroups of GLO1 rs4746 polymorphism. In conclusion, this is the first study describing significant relationship of FN3K (rs1056534) and (rs3848403) polymorphisms with concentration of sRAGE in patients with diabetes.

Skin autofluorescence relates to soluble receptor for advanced glycation end-products and albuminuria in diabetes mellitus

The aim of this study was to compare skin autofluorescence caused by advanced glycation end-products (AGEs) with biochemical markers of endothelial dysfunction and soluble receptor for AGEs (sRAGE) in patients with diabetes. Skin autofluorescence (AF) assessed by AGE-Reader was evaluated with sRAGE and other biochemical parameters in 88 patients with diabetes (47 Type 1/T1DM/ and 41 Type 2/T2DM/) and 20 controls. Skin AF was significantly higher in T1DM and T2DM in comparison to controls (2.39 ± 0.54, 2.63 ± 0.73 versus 1.96 ± 0.33 AU; P < 0.0001). Positive correlation of AF with sRAGE was detected in T1DM and T2DM (r = 0.37, P < 0.02 and r = 0.60, P < 0.0001), but not in controls. Significantly higher AF values were found in patients with positive albuminuria as compared to those with normal albuminuria. Similarly, higher AF was detected in patients with endothelial dysfunction expressed by vWF, ICAM-1, and VCAM-1. Multiple regression analysis revealed independent association of skin AF with age, sRAGE, and albumin-creatinine ratio in patients with diabetes (R (2) = 0.38). Our study confirms that AF is elevated in patients with diabetes, especially with positive albuminuria and endothelial dysfunction. The strong and independent relationship between AF and sRAGE supports the idea that AF may reflect AGEs/RAGE interactions. The exact mechanism remains to be established.

Relationship of soluble RAGE and RAGE ligands HMGB1 and EN-RAGE to endothelial dysfunction in type 1 and type 2 diabetes mellitus

Receptor for advanced glycation end-products (RAGE) plays the essential role in the pathogenesis of diabetic vascular complications. The aim of the study was to compare concentration of soluble RAGE and its ligands (EN-RAGE and HMGB1) with different biochemical parameters in Type 1 (T1DM) and Type 2 (T2DM) diabetes mellitus.Total number of 154 persons (45 T1DM, 68 T2DM, 41 controls) was examined and concentrations of sRAGE, EN-RAGE and HMGB1 were measured and compared to diabetes control, albuminuria, cell adhesion molecules and metalloproteinases (MMPs).Mean serum sRAGE concentration was higher in T1DM as compared to controls (1137±532 ng/l vs. 824±309 ng/l, p<0.01). Similarly, EN-RAGE was significantly higher in both diabetic groups (p<0.001) and HMGB1 concentrations were elevated in T2DM patients (p<0.01). Significant relationship was found between MMP9 and HMGB1 and EN-RAGE in diabetic patients. Inverse relationship was observed between MMP2 and MMP9 in both types of diabetic patients (r= - 0.602, p<0.002 and r= - 0.771, p<0.001). Significant positive correlation was found between sRAGE and ICAM-1, VCAM-1 or vWF (p<0.01 to p<0.001).We conclude that serum sRAGE and RAGE ligands concentrations reflect endothelial dysfunction developing in diabetes.

Prevalence and Pathogenicity of Cryptosporidium suis in Pre- and Post-weaned Pigs

A total of 4338 faecal samples, 135 of sows, 3368 of pre-weaned and 835 of post-weaned piglets from eight farms in South Bohemia, Czech Republic were collected and examined for Cryptosporidium infection. No sow, but 5.7% pre-weaned and 24.1% post-weaned piglets were positive for Cryptosporidium infection. No relationship was found between diarrhoea and Cryptosporidium infection in any of the different age groups (pre- and post-weaned piglets). Four piglets, which were sporadically shedding cryptosporidia in faeces, were necropsied. Neither clinical signs of diarrhoea nor macroscopical changes were found. Histologically, a moderate infection of cryptosporidia was detected in the glandular epithelium along the large intestine, with predisposition to the ansa centralis of the colon. No inflammatory response in the lamina propria was observed. Cryptosporidia were also commonly found in the glandular epithelium of submucosal lymphoglandular complexes in the colon. Cryptosporidium isolates from all farms were identified as Cryptosporidium suis using molecular markers (SSU rRNA). All of the C. suis strains obtained were larger [6.2 (6.0-6.8) x 5.5 (5.3-5.7) microm] than any isolate described so far [4.6 (4.4-4.9) x 4.2 (4.0-4.3) microm] and did not appear to be infective for neonatal BALB/c mice.