LIN28 Expression in Rat Spinal Cord After Injury

Ying Yue,Tao Tao,Aihong Li,Xingxing Gu,Dongmei Zhang,Shengyang Jiang,Xinming Wu,Aisong Guo,Hongbing Cheng,Xiaopeng Xia

doi:10.1007/s11064-014-1278-2

Abstract

LIN28, an RNA-binding protein, is known to be involved in the regulation of many cellular processes, such as embryonic stem cell proliferation, cell fate succession, developmental timing, and oncogenesis. However, its expression and function in central nervous system still unclear. In this study, we performed an acute spinal cord contusion injury (SCI) model in adult rats and investigated the dynamic changes of LIN28 expression in spinal cord. Western blot and immunohistochemistry analysis revealed that LIN28 was present in normal spinal cord. It gradually increased, reached a peak at 3 day, and then nearly declined to the basal level at 14 days after SCI. Double immunofluorescence staining showed that LIN28 immunoreactivity was found in neurons, astrocytes and a handful of microglia. Interestingly, LIN28 expression was increased predominantly in astrocytes but not in neurons. Moreover, the colocalization of LIN28 and proliferating cell nuclear antigen was detected after injury. Western blot showed that LIN28 participated in lipopolysaccharide (LPS) induced astrocytes inflammatory responses by NF-κB signaling pathway. These results suggested that LIN28 may be involved in the pathologic process of SCI, and further research is needed to have a good understanding of its function and mechanism.

Highlights

Spinal cord injury (SCI) is a devastating and common neurologic disorder that has profound influences on modern society from physical, psychosocial, and socioeconomic perspectives [1,2,3]
Western blot showed that LIN28 participated in lipopolysaccharide (LPS) induced astrocytes inflammatory responses by NFjB signaling pathway. These results suggested that LIN28 may be involved in the pathologic process of spinal cord contusion injury (SCI), and further research is needed to have a good understanding of its function and mechanism
To further testify that LIN28 expression is related to the SCI, we investigated the effects of contusion induced by dropping the rod from different heights (0, 6.25, 12.5, 25,50, 75, 100, and 125 mm) at day 3 after SCI and observed the expression patterns of LIN28 by western blot

Summary

Introduction

Spinal cord injury (SCI) is a devastating and common neurologic disorder that has profound influences on modern society from physical, psychosocial, and socioeconomic perspectives [1,2,3]. Secondary injury of SCI may result from spinal cord edema, ischemia, free radical damage, electrolyte imbalance, excitotoxicity, inflammatory injury, and apoptosis [6,7,8,9] These factors cause astrocytes proliferation and reactive gliosis, resulting in the formation of a dense astrocytic scar [10, 11]. This glial scar provides a physical and biochemical barrier to regeneration and plasticity, and acts as a source of multiple inhibitory factors that affect functional recovery from SCI [12, 13]. It is remain to be further elucidated about the molecular mechanisms of post traumatic pathology of spinal cord

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Results

Conclusion