Cross-species replication of a resistin mRNA QTL, but not QTLs for circulating levels of resistin, in human and baboon
HEREDITY
Authors: Tejero, M. E.; Voruganti, V. S.; Proffitt, J. M.; Curran, J. E.; Goring, H. H. H.; Johnson, M. P.; Dyer, T. D.; Jowett, J. B.; Collier, G. R.; Moses, E. K.; MacCluer, J. W.; Mahaney, M. C.; Blangero, J.; Comuzzie, A. G.; Cole, S. A.
Abstract
Resistin has been associated with inflammation and risk for cardiovascular disease. We previously reported evidence of a QTL on chromosome 19p 13 affecting the abundance of resistin (RETN) mRNA in the omental adipose tissue of baboons (L0D score 3.8). In this study, whole genome transcription levels were assessed in human lymphocyte samples from 1240 adults participating in the San Antonio Family Heart Study, using the Sentrix Human-6 Expression Beadchip. Lymphocytes were surveyed, as it has been proposed that their expression levels may reflect those in harder to ascertain tissues, such as adipose tissue, that are thought to be more directly relevant to disease processes. A genome-wide scan was conducted to detect loci affecting RETN mRNA levels. We obtained significant evidence for a QTL influencing the RETN expression (LOD score 10.7) on chromosome 19p. This region is orthologous/homologous to the region previously localized on baboon chromosome 19. The strongest positional candidate gene in this region is the structural gene for resistin, itself. We also found evidence for a QTL influencing resistin protein levels (LOD score 5.3) on chromosome 14q. This differs from our previously reported QTL on chromosome 18 in baboons. The different QTLs for circulating protein suggests that post-translational processing and turnover may be influenced by different or multiple genes in baboons and humans. The parallel findings of a cis-eQTL for RETN mRNA in baboon omental tissue and human lymphocytes lends support to the strategy of using lymphocyte gene expression levels as a surrogate for gene expression levels in other tissues.
Serum Resistin, Cardiovascular Disease and All-Cause Mortality in Patients with Type 2 Diabetes
PLOS ONE
Authors: Menzaghi, Claudia; Bacci, Simonetta; Salvemini, Lucia; Mendonca, Christine; Palladino, Giuseppe; Fontana, Andrea; De Bonis, Concetta; Marucci, Antonella; Goheen, Elizabeth; Prudente, Sabrina; Morini, Eleonora; Rizza, Stefano; Kanagaki, Alyssa; Fini, Grazia; Mangiacotti, Davide; Federici, Massimo; De Cosmo, Salvatore; Pellegrini, Fabio; Doria, Alessandro; Trischitta, Vincenzo
Abstract
Background: High serum resistin has been associated with increased risk of cardiovascular disease in the general population, Only sparse and conflicting results, limited to Asian individuals, have been reported, so far, in type 2 diabetes. We studied the role of serum resistin on coronary artery disease, major cardiovascular events and all-cause mortality in type 2 diabetes. Methods: We tested the association of circulating resistin concentrations with coronary artery disease, major cardiovascular events (cardiovascular death, non-fatal myocardial infarction and non-fatal stroke) and all-cause mortality in 2,313 diabetic patients of European ancestry from two cross-sectional and two prospective studies. In addition, the expression of resistin gene (RETN) was measured in blood cells of 68 diabetic patients and correlated with their serum resistin levels. Results: In a model comprising age, sex, smoking habits, BMI, HbA1c, and insulin, antihypertensive and antidyslipidemic therapies, serum resistin was associated with coronary artery disease in both cross-sectional studies: OR (95%CI) per SD increment = 1.35 (1.101.64) and 1.99 (1.552.55). Additionally, serum resistin predicted incident major cardiovascular events (HR per SD increment = 1.31; 1.101.56) and all-cause mortality (HR per SD increment = 1.16; 1.061.26). Adjusting also for fibrinogen levels affected the association with coronary artery disease and incident cardiovascular events, but not that with all cause-mortality. Finally, serum resistin was positively correlated with RETN mRNA expression (rho = 0.343). Conclusions: This is the first study showing that high serum resistin (a likely consequence, at least partly, of increased RETN expression) is a risk factor for cardiovascular disease and all-cause mortality in diabetic patients of European ancestry.