High-Normal C-Reactive Protein Levels Do Not Affect the Vitamin A Transport Complex in Serum of Children and Adolescents with Type 1 Diabetes

Abstract

Type 1 diabetes is associated with the presence of inflammation, which in turn affects parameters used to assess the vitamin A status. In the present study, we evaluated the influence of inflammatory status on retinol, retinol-binding protein 4 (RBP4), and transthyretin (TTR) in children and adolescents with type 1 diabetes. A total of 40 children with type 1 diabetes (median age, 14.2 y; median BMI-SDS, 0.53; median diabetes duration, 5.8 y; median HbA 1c , 7.3%) and 46 healthy subjects (median age, 12.8 y; median BMI-SDS, 0.34; median HbA 1c 5.4%) were recruited. Serum levels of CRP were significantly elevated (p ϭ 0.005) and retinol concentrations were significantly lower (p ϭ 0.02) in children and adolescents with type 1 diabetes compared with healthy subjects. Serum RBP4 and TTR showed no differences between the groups. Healthy children with CRP levels above 0.6 mg/L had significant lower levels of retinol (p ϭ 0.03). This was not observed in children with type 1 diabetes. The results suggest that, in contrast to healthy children, minor CRP elevation does not affect vitamin A transport complex in serum of children with type 1 diabetes. (Pediatr Res 62: 741-745, 2007)

Low Serum Levels of Prealbumin, Retinol Binding Protein, and Retinol Are Frequent in Adult Type 1 Diabetic Patients

“…Except in the paper of Este et al [9], all published studies coincide in reporting PA levels in the lower normal range in both children and adults, with T1D [1, 2, 5–8]. Our findings match up with published data except in the fact that we do find levels below normality in half of the analyzed patients.…”

“…When comparing T1D children with control groups, Baena et al [3] describe higher levels, Espe et al [9] and Gebre-Medhin et al [16] describe similar levels, and Kemp et al [8] describe lower levels. Focused on T1D adults, the only studies published agree with our work in showing decreased RBP levels [11, 17].…”

“…Compared to controls, Baena et al [3] observed higher RBP levels and lower retinol levels and Espe et al [9] referred normal RBP and lower retinol levels, while Hozumi et al [10] reported that no differences could be found among groups. (ii) In adults, it has been described that T1D patients do display lower levels of RBP and retinol than their healthy counterparts [11–13].…”

“…In this respect, while results are far from being uniform, it is accepted that local low insulin levels in liver do decrease hepatic synthesis of both PA and RBP [2, 3, 6–9, 14]. …”

“…The cause of this fact has been attributed to low carotene to retinol conversion rates in those patients [12, 13] as well as an increased retinol consumption, derived from the increased need of T1D patients to eliminate free reactive oxygen species [8]. However, unlike the case with PA or RBP, no association has been found between glycemic control and retinol levels [8, 9, 12, 13]; instead, a positive correlation was found between retinol and the triglyceride levels [9]. …”