Telegin Georgii B, Minakov Alexey N, Chernov Aleksandr S, Kazakov Vitaly A, Kalabina Elena A, Manskikh Vasily N, Asyutin Dmitry S, Belogurov Alexey A, Gabibov Alexander G, Konovalov Nikolay A, Spallone Aldo
Branch of Shemyakin and Ovchinnikov, Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia.
A.N. Belozersky Institute of Physico-Chemical Biology, M.V. Lomonosov Moscow State University, Moscow, Russia.
Front Surg. 2021 Jul 15;8:607551. doi: 10.3389/fsurg.2021.607551. eCollection 2021.
According to the World Health Organization, every year worldwide up to 500,000 people suffer a spinal cord injury (SCI). Various animal biomodels are essential for searching for novel protocols and therapeutic approaches for SCI treatment. We have developed an original model of post-traumatic spinal cord glial scarring in rats through cryoapplication. With this method the low-temperature liquid nitrogen is used for the cryodestruction of the spinal cord tissue. Forty-five Sprague Dawley (SD) non-linear male rats of the Specific-pathogen-free (SPF) category were included in this experimental study. A Th13 unilateral hemilaminectomy was performed with dental burr using an operating microscope. A specifically designed cryogenic probe was applied to the spinal cord for one minute through the created bone defect. The animals were euthanized at different time points ranging from 1 to 60 days after cold-induced injury. Their Th12-L1 vertebrae with the injured spinal cord region were removed "e" for histological examination. Our data demonstrate that cryoapplication producing a topical cooling around-20°C, caused a highly standardized transmural lesion of the spinal cord in the dorsoventral direction. The lesion had an "hour-glass" shape on histological sections. During the entire study period (days 1-60 of the post-trauma period), the necrotic processes and the development of the glial scar (lesion evolution) were contained in the surgically approached vertebral space (Th13). Unlike other known experimental methods of SCI simulation (compression, contusion, etc.), the proposed technique is characterized by minimal invasiveness, high precision, and reproducibility. Also, histological findings, lesion size, and postoperative clinical course varied only slightly between different animals. An original design of the cryoprobe used in the study played a primary role in the achieving of these results. The spinal cord lesion's detailed functional morphology is described at different time points (1-60 days) after the produced cryoinjury. Also, changes in the number of macrophages at distinct time points, neoangiogenesis and the formation of the glial scar's fibrous component, including morphodynamic characteristics of its evolution, are analyzed. The proposed method of cryoapplication for inducing reproducible glial scars could facilitate a better understanding of the self-recovery processes in the damaged spinal cord. It would be evidently helpful for finding innovative approaches to the SCI treatment.
根据世界卫生组织的数据，全球每年多达50万人遭受脊髓损伤（SCI）。各种动物生物模型对于寻找脊髓损伤治疗的新方案和治疗方法至关重要。我们通过冷冻应用开发了一种大鼠创伤后脊髓胶质瘢痕形成的原始模型。使用这种方法，低温液氮用于脊髓组织的冷冻破坏。本实验研究纳入了45只无特定病原体（SPF）级别的Sprague Dawley（SD）雄性大鼠。使用牙科钻在手术显微镜下进行T13单侧半椎板切除术。通过创建的骨缺损将专门设计的低温探头应用于脊髓一分钟。在冷诱导损伤后的1至60天的不同时间点对动物实施安乐死。取出其带有损伤脊髓区域的T12-L1椎骨用于组织学检查。我们的数据表明，产生约-20°C局部冷却的冷冻应用导致脊髓在背腹方向上出现高度标准化的透壁损伤。该损伤在组织学切片上呈“沙漏”形。在整个研究期间（创伤后第1至60天），坏死过程和胶质瘢痕的形成（损伤演变）局限于手术涉及的椎间隙（T13）。与其他已知的脊髓损伤模拟实验方法（压迫、挫伤等）不同，所提出的技术具有微创性小、精度高和可重复性的特点。此外，不同动物之间的组织学结果、损伤大小和术后临床过程仅有轻微差异。研究中使用的低温探头的原始设计在取得这些结果中起了主要作用。在产生冷冻损伤后的不同时间点（1至60天）描述了脊髓损伤的详细功能形态。还分析了不同时间点巨噬细胞数量的变化、新生血管形成以及胶质瘢痕纤维成分的形成，包括其演变的形态动力学特征。所提出的用于诱导可重复性胶质瘢痕的冷冻应用方法有助于更好地理解受损脊髓的自我恢复过程。这显然有助于找到脊髓损伤治疗的创新方法。
