Hyperglycemia is one of the most important clinical features of
burn patients. Previous reports had demonstrated that
miRNA was involved in regulating
glucose metabolism in various diseases such as diabetes and
obesity. Our current study discovered the relationship between miR-194 and
hyperglycemia in
burn rats via suppressing
insulin-like growth factor 1 receptor (IGF-IR). We found that the fasting
blood glucose was significantly increased in rats of the
burn group, and
protein expression of IGF-IR was attenuated in response to
burn injury. Similar to the results of animal experiments, miR-194 expression was significantly elevated and IGF-IR
protein level was suppressed in L6 cells treated with serum from
burn rats compared with those treated by serum from
sham rats. However, IGF-IR
mRNA level was comparable between
burn and
sham rats, suggesting that IGF-IR may be downregulated at the translation level. Further experiments revealed that miR-194 was significantly increased in
burn rats compared with
sham rats using
miRNA array and real-time polymerase chain reaction (PCR) assay. And IGF-IR
protein expression was reduced in L6 cells transfected with miR-194 plasmid.
Insulin-like growth factor 1 receptor expression was also repressed and fasting
blood glucose was increased in rats injected with miR-194 plasmid. In general, we have identified a novel function of miR-194 in modulating
burn-induced
hyperglycemia via suppressing the expression of IGF-IR.