ACTA ENDOCRINOLOGICA (BUC)

Context. Abnormally increased hepatic glucose production contributes to hyperglycemia in diabetes. Interventions that suppress hepatic gluconeogenesis should be beneficial in improving glycemic control in patients with diabetes. Objectives. It has been suggested that hepatic FTO is involved in glycemic control by regulating gluconeogenesis. Both FTO and activating transcription factor 4 (ATF4) positively regulate the expression of gluconeogenic genes in the liver, suggesting the possibility that ATF4 mediates the stimulatory effect of FTO on hepatic gluconeogenesis. The present study aimed to determine the effect of altered expression or activity of FTO on Atf4 and gluconeogenic gene expression in hepatocyte cells. Methods. Mouse hepatocyte AML12 cells were treated with the FTO inhibitor rhein or transfected with an FTO-expressing plasmid. Levels of gluconeogenic glucose- 6-phosphatase (G6pc) and Atf4 mRNA and protein were measured. Results. Rhein treatment significantly reduced G6pc mRNA levels as well as Atf4 mRNA and protein levels. Conversely, enhanced FTO expression caused an increase in G6pc and Atf4 mRNA levels. Conclusions. These findings support the hypothesis that hepatic FTO participates in the regulation of hepatic gluconeogenic gene and ATF4 expression. Reducing the activity of the hepatic FTO-ATF4 pathway may be beneficial in reducing hepatic glucose production and ameliorating hyperglycemia in diabetes.

In response to increasing interest of the European Commission on large-scale\r\ngenotyping for complex diseases, including variability in ethnic minorities in\r\nEurope (HEALTH-2009-4.3.3-1), at the end of 2008 we composed the\r\nHAPLOGENDIS consortium with partners from Russia and European countries. A\r\nfirst program (SICA) was proposed in cooperation with Russian Federal Agency for\r\nScience and Innovation, focusing on comparative population genetics on diseases\r\naccompanied by insulin resistance. Beside the specificity in analyzing the human\r\ngenome with SNP (single nucleotide polymorphism) and defining haplotype\r\nstructure of genes, the program rises new hypotheses which directly link\r\ncolonization of Europe at the Neolithic period from Eastern Ukraine or Anatolia\r\nwith the development of agriculture and major dietary and life style changes that\r\nmay have an impact on the genome. Although there will be many occasions to\r\nreview both genetic and clinical detailed aspects, this short note will expose some\r\nunifying ideas that joint these partners.