Ribonucleosides from tRNA in Hyperglycemic Mammalian Cells and Diabetic Murine Cardiac Models

Dodson, Taylor A; Nieuwoud, Stephen; Morse, Chase N; Liu, Chao; Pierre, Valinteshley; Senyo, Samuel E; Prestwich, Erin G

Aims: Cardiomyopathy is a diabetic comorbidity with few molecular targets. To address this, we evaluated transfer RNA (tRNA) modifications in the diabetic heart because tRNA modifications have been implicated in diabetic etiologies. Main methods: tRNA was isolated from aorta, apex, and atrial tissue of healthy and diabetic murine hearts and related hyperglycemic cell models. tRNA modifications and canonical ribonucleosides were quantified by liquid- chromatography tandem mass spectrometry (LC-MS/MS) using stable isotope dilution. Correlations between ribonucleosides and diabetic comorbidity pathology were assessed using statistical analyses. Key findings: Total tRNA ribonucleoside levels were analyzed from cell types and healthy and diabetic murine heart tissue. Each heart structure had characteristic ribonucleoside profiles and quantities. Several ribonucleo- sides were observed as significantly different in hyperglycemic cells and diabetic tissues. In hyperglycemic models, ribonucleosides N4-acetylcytidine (ac4C), 5-methoxycarbonylmethyl-2-thiouridine (mcm5s2U), 5-meth- ylcytidine (m5C), and N1-methylguanosine (m1G) were anomalous. Specific tRNA modifications known to be on murine tRNAIni(CAU) were higher in diabetic heart tissue which suggests that tRNA modifications could be regulating translation in diabetes. Significance: We identified tRNA ribonucleosides and tRNA species associated with hyperglycemia and diabetic etiology.

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