Department of Radiology, Second Xiangya Hospital of Central South University, Changsha, China.
School of Life Science and Technology, Xidian University, Xi'an, 710071, China.
Drug Alcohol Depend. 2021 Feb 1;219:108485. doi: 10.1016/j.drugalcdep.2020.108485. Epub 2020 Dec 21.
The striatum mediates reward processing in addiction, and previous fMRI (functional Magnetic Resonance Imaging) studies have revealed abnormal striatofrontal functional connectivity in heroin addiction. However, little is known about whether there is abnormal structural connectivity of the striatal circuit in heroin addiction. This study investigated the structural connectivity of striatal circuits in abstinent heroin-dependent individuals (HDIs) without methadone treatment.
Forty-three (age: 38.8 ± 7.1) male HDIs and twenty-one (age: 42.4 ± 7.9) matched healthy controls underwent high-resolution T1 and whole-brain diffusion tensor imaging (64 directions) magnetic resonance imaging. Connectivity-based seed classification probabilistic tractography was used to detect the tract strengths of striatal circuits with 10 a priori target masks. Tract strengths were compared between groups and correlated with impulsivity behavior, evaluated using the Barratt Impulsivity Scale (BIS), and craving, measured on visual analogue scale (VAS).
HDIs showed significantly weaker tract strength of the left striatum-medial orbitofrontal cortex (mOFC) (Bonferroni corrected, p < 0.05/20 = 0.0025) and significantly higher BIS total, attention, motor, and non-planning scores (Bonferroni corrected, p < 0.05/4 = 0.0125) than controls. In HDIs, negative correlations were observed between the left striatum- mOFC tract strengths and the BIS total, attention and non-planning scores (r=-0.410, p = 0.005; r=-0.432, p = 0.003; r=-0.506, p<0.001) and between the right striatum-posterior cingulate cortex (PCC) tract strengths and craving scores (r=-0.433, p = 0.009) in HDIs.
HDIs displayed decreased structural connectivity of the striatum-mOFC circuit and higher impulsivity. Higher impulsive behavior was associated with decreased left striatal circuit connectivity. These findings suggest that the striatal circuit tract strengths might be a novel potential biomarker in heroin and, potentially, general opioid addiction.
纹状体介导成瘾中的奖励处理，先前的 fMRI（功能磁共振成像）研究表明，海洛因成瘾者的纹状体-额皮质功能连接异常。然而，对于海洛因成瘾者是否存在纹状体回路的异常结构连接知之甚少。本研究调查了未接受美沙酮治疗的戒断海洛因依赖个体（HDI）的纹状体回路的结构连接。
43 名（年龄：38.8±7.1）男性海洛因依赖者和 21 名（年龄：42.4±7.9）匹配的健康对照者接受高分辨率 T1 和全脑弥散张量成像（64 个方向）磁共振成像。使用基于连接的种子分类概率追踪技术，使用 10 个先验目标掩模检测纹状体回路的束强度。比较组间束强度，并与使用巴雷特冲动量表（BIS）评估的冲动行为（视觉模拟量表（VAS）测量的渴望）相关。
HDI 显示左侧纹状体-内侧眶额皮质（mOFC）的束强度明显减弱（Bonferroni 校正，p<0.05/20=0.0025），BIS 总分、注意力、运动和非计划评分明显升高（Bonferroni 校正，p<0.05/4=0.0125）与对照组相比。在 HDI 中，左侧纹状体-mOFC 束强度与 BIS 总分、注意力和非计划评分呈负相关（r=-0.410，p=0.005；r=-0.432，p=0.003；r=-0.506，p<0.001），右侧纹状体-后扣带回皮质（PCC）束强度与渴望评分呈负相关（r=-0.433，p=0.009）。
HDI 显示纹状体-mOFC 回路的结构连接减少和冲动性增加。较高的冲动行为与左侧纹状体回路连接减少有关。这些发现表明，纹状体回路束强度可能是海洛因和潜在的一般阿片类药物成瘾的新型潜在生物标志物。
