Objective: To study the protective effect of vitamin A on residual pancreatic β cell function in children with type 1 diabetes mellitus (T1DM) and its mechanism.
Methods: A total of 46 children with T1DM (with a course of disease of 0.5-1 year) were randomly divided into an intervention group and a non-intervention group (n=23 each). The children in both groups were given insulin treatment, and those in the intervention group were also given vitamin A at a daily dose of 1 500-2 000 IU. A total of 25 healthy children were enrolled as the control group. The daily dose of insulin was calculated for the children with T1DM, and the serum levels of glycosylated hemoglobin (HbA1C), stimulated C-peptide, vitamin A, and interleukin-17 (IL-17) were measured before intervention and 3 months after intervention.
Results: Before vitamin A intervention, the intervention group and the non-intervention group had a significantly lower serum level of vitamin A and a significantly higher level of IL-17 than the control group (P<0.01). After 3 months of intervention, the intervention group had significantly lower serum IL-17 level and insulin dose and a significantly higher level of stimulated C-peptide than the non-intervention group (P<0.05).
Conclusions: Vitamin A may protect residual pancreatic β cell function, possibly by improving the abnormal secretion of IL-17 in children with T1DM.
目的: 探讨维生素A对1型糖尿病（T1DM）残存胰岛β细胞功能的保护作用及其机制。
方法: 46例T1DM患儿（病程0.5~1年）随机分为干预组（23例）和未干预组（23例），两组均予以胰岛素治疗，干预组服用维生素A（每日1 500~2 000 IU），并以25例健康儿童为对照组。计算两组T1DM患儿的每日胰岛素用量，并分别于干预前、干预3个月后检测糖化血红蛋白（HbA1C）、激发后血清C-肽、血清维生素A、血清白细胞介素-17（IL-17）水平。
结果: 维生素A干预前，干预组和未干预组T1DM患儿的血清维生素A水平均低于对照组（P < 0.01），其IL-17水平均高于对照组（P < 0.01）。维生素A干预3个月后，干预组血清IL-17水平、每日胰岛素用量低于未干预组（P < 0.05），激发后C肽水平高于未干预组（P < 0.05）。
结论: 维生素A可以保护残存胰岛β细胞功能，机制可能与维生素A改善T1DM患儿IL-17的异常分泌有关。