Netrin-1: A Serum Marker Predicting Cognitive Impairment after Spinal Cord Injury

Abstract

Objective. Although cognitive impairment has received more attention in recent years as a result of spinal cord injury (SCI), the pathogenic process that causes it is still unknown. The neuroprotective effects of Netrin as a family of laminin-related secreted proteins were discovered. The purpose of this study was to determine the changes of serum Netrin-1 after SCI and its relationship with cognitive impairment. Methods. 96 SCI patients and 60 controls were included in our study. We collected baseline data from all participants, measured their serum Netrin-1 levels, and followed up their cognitive levels 3 months later. Results. The clinical baseline values between the control and SCI groups were not significantly different ( <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" id="M1"> <a:mi>p</a:mi> <a:mo>&gt;</a:mo> <a:mn>0.05</a:mn> </a:math> ). However, the serum Netrin-1 level in the SCI group was significantly lower than that in the control group ( <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" id="M2"> <c:mn>528.4</c:mn> <c:mo>±</c:mo> <c:mn>88.3</c:mn> </c:math> pg/ml vs. <e:math xmlns:e="http://www.w3.org/1998/Math/MathML" id="M3"> <e:mn>673.5</e:mn> <e:mo>±</e:mo> <e:mn>97.2</e:mn> </e:math> pg/ml, <g:math xmlns:g="http://www.w3.org/1998/Math/MathML" id="M4"> <g:mi>p</g:mi> <g:mo>&lt;</g:mo> <g:mn>0.05</g:mn> </g:math> ). According to the quartile level of serum Netrin-1 level in the SCI group, we found that with the increase of serum Netrin-1 level, the MoCA score also increased significantly ( <i:math xmlns:i="http://www.w3.org/1998/Math/MathML" id="M5"> <i:mi>p</i:mi> <i:mo>&lt;</i:mo> <i:mn>0.001</i:mn> </i:math> ), indicating that the serum Netrin-1 level was positively correlated with the MoCA score after SCI. After controlling for baseline data, multiple regression analysis revealed that Netrin-1 remained an independent risk factor for cognitive impairment after SCI (=0.274, <k:math xmlns:k="http://www.w3.org/1998/Math/MathML" id="M6"> <k:mi>p</k:mi> <k:mo>=</k:mo> <k:mn>0.036</k:mn> </k:math> ). Conclusions. Netrin-1 may be a neuroprotective factor for cognitive impairment, which may serve as a serum marker to predict cognitive impairment after SCI.